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3.6: Negligence- Causation

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    Causation in Fact versus Proximate Cause. There are two distinct inquiries to satisfy the causation element for negligence. The first, “cause in fact,” poses a factual causation (did this thing cause that injury) and the second, “proximate cause,” poses a policy question (given that this thing did cause that injury, should the law limit or find liability in this case?) The first question is descriptive; the second question is normative. Proximate cause functions somewhat like duty in that both can operate as liability-limiting principles except that duty is a question of law determined by the judge and often used as a gatekeeping mechanism; proximate cause is a question of fact decided by the jury and thus usually requires development of a fuller factual record. Both causation and proximate cause are questions of fact determined by the jury. One might reasonably ask why cause in fact would be a jury question given that it can sometimes involve intensely complicated fact patterns. The plaintiff may have to describe complex manufacturing processes or be able to trace harm back to exposure to chemicals, for example, thus requiring the jury to ascertain the existence of some sort of careless mistake and the likelihood that it caused the plaintiff’s injury. One might also reasonably ask why proximate cause would be a jury question given that it requires a clear policy determination and judges seem likelier to be versed in making policy determinations. We will return to this question below when we discuss proximate cause in the next chapter. This introductory discussion deliberately defers the greater complexities associated with causation, such as when there are multiple sufficient causes or when causes may combine to create concurrent consequences. The initial focus here is on the most foundational understanding of causation in fact.

    Causation in fact is often described using a counterfactual inquiry that begins with the defendant’s breach of conduct, whatever it constituted. Was that breach the “sine qua non” (Latin for the thing “without which, there would be none”)? That is, if we subtracted the defendant’s unreasonable conduct from the facts of the case and the harm would not have happened, then causation in fact is met. If the breach of due care, when removed, makes no difference to the plaintiff’s injuries, causation in fact is typically not met. In some cases a different test may be required because of multiple tortfeasors or causes. But this initial test of “but-for causation” is the primary means of satisfying the first prong of the causation element.

    Questions or Areas of Focus for the Readings

    • Causation in fact is a factual question for the jury. As you read cases of varying kinds and complexity, do they seem applicable amenable to jury decision making?
    • If certain kinds of harm make causation harder, more expensive, or impossible to prove, what mechanisms or outcomes seem appropriate to adopt?
    • Causation in fact is distinguished from proximate cause in that the former inquiry is “factual” and the latter is normative, based on policy considerations, as you will learn in a subsequent set of readings. However, the distinction between them suggests that causation in fact possesses fewer policy issues. Consider whether the causation element seems distinguishable from tort law’s more explicitly policy-driven questions.

    (334 Or. 264) (Facts excerpted from trial and appellate opinions)

    [***] “Gary Garrison was severely injured in a fall at the Fryrear transfer station, which is owned and operated by Deschutes County. The transfer station was designed and built using ‘Z-wall construction’, which consists of a concrete upper slab with a 14.5-foot retaining wall that drops to a concrete lower slab. The design allows persons using the transfer station to back their vehicles onto the upper slab and dump their garbage into semi-truck trailers that have been placed on the lower slab. There is a seven-inch railroad tie at the edge of the upper slab that serves as a barrier to warn drivers not to back their vehicles any further. At the time of Garrison’s fall, there were no other barriers or fences on the upper slab, and there were no signs warning users of the danger of falling from the upper to the lower one.

    On the day that Garrison was injured, he and his wife had driven to the transfer station in their pickup with a load of refuse. Both had been to the transfer station before and, as at those earlier times, Garrison backed the pickup up to the railroad tie barrier and lowered the tailgate. When the tailgate was lowered, it protruded out over the edge of the upper slab. Both Garrison and his wife were aware of the distance of the drop from the upper to the lower slab and had discussed the importance of being careful so as not to fall. Garrison stood in the back of the pickup and threw the refuse over the edge and into the trailer below. When he was finished, he grabbed a lumber rail on *268 the back of the pickup and attempted to swing out onto the pavement of the upper slab. In doing so, he fell to the pavement of the lower slab, suffering severe injuries to his face, head, arms and chest.” 162 Or. App. at 162-63.

    Plaintiffs’ amended complaint alleged that the county was negligent “[i]n failing to maintain a premises which is reasonably safe from dangers which were known or, in the exercise of reasonable care, should have been known to defendant by placing fences, barriers, or other protective devices next to the wall to prevent individuals from falling,” and “[i]n failing to protect invitees from unreasonably dangerous conditions on the premises which were known to the defendant or, in the exercise of reasonable care, should have been known to the defendant by posting signs or other warning devices warning of the immediate drop off.” [***]

    [P]laintiffs contended that the county had a duty to warn of any known dangerous condition on its land and had failed to do so. [***]

    The trial court [***] rejected plaintiffs ‘failure-to-warn claim, based on what the court termed a “lack of causation.” The court observed that the danger was open and obvious and, in light of plaintiffs’ deposition testimony that they were well aware of the risk, the failure to warn did not expose them to any greater risk of harm than would have been present had they been warned. Accordingly, the court concluded that there was no genuine issue of fact or evidence in the record from which a reasonable juror could have found that there was a causal link of any kind between the failure to warn and the accident that befell Garrison [***] [T]he Court of Appeals agreed that the danger was an obvious one, that plaintiffs were fully aware of the danger, and, consequently, that the absence of a warning did not expose plaintiffs to any greater risk of harm than if they had been warned.

    Plaintiffs’ first and third specifications of negligence, concerning the county’s allegedly negligent design of the transfer station,[1] invoke the general common-law responsibility of all persons to avoid conduct that creates a specific *272 risk of injury to others, as well as the special duties that a possessor of land owes to business invitees. In similar cases involving private landowners and occupiers, this court typically begins by examining the claims to determine whether the property owner’s alleged conduct was unreasonable in the circumstances and created a foreseeable, unreasonable risk of harm to the plaintiff. [c] A private landowner or occupier of land in a position similar to the county’s would be required to take care to protect patrons on the premises from injuries resulting from known, dangerous conditions on the premises or, at least, to warn them of the danger. Woolston v. Wells, 297 Or. 548, 557-58 (1984). [***]

    Plaintiffs argue that Woolston stands for the proposition that even obvious hazards must be considered within a scheme of comparative fault. The court there stated:

    “Each party is held to the same standard of care with respect to common law negligence. Negligence is conduct falling below the standard established for the protection of others, or oneself, against unreasonable risk of harm. The standard of care is measured by what a reasonable person of ordinary prudence would, or would not, do in the same or similar circumstances.” * * *

    In general, it is the duty of the possessor of land to make the premises reasonably safe for the invitee’s visit. The possessor must exercise the standard of care above stated to discover conditions of the premises that create an unreasonable risk of harm to the invitee. The possessor must exercise that standard of care either to eliminate the condition creating that risk or to warn any foreseeable invitee of the risk so as to enable the invitee to avoid the harm. The invitee is required to exercise that same standard of care in avoiding harm from a condition of the premises of which he knows, or, in the exercise of that standard of care, of which he should know. *279

    Instructions to the jury should be framed in terms of that standard of care. The jury will thereby be enabled to determine whether any given party is at fault and if both are at fault to compare that fault as the statute commands. In determining and comparing fault, the jury must necessarily consider the obviousness of danger and the ease or difficulty with which harm to the plaintiff from that danger could be avoided by either party.” 297 Or. at 557-58, (citation omitted).

    Plaintiffs contend that the Court of Appeals’ holding is inconsistent with the foregoing directive. They assert that the Court of Appeals effectively held, as a matter of law, that there is no “causal link” when the invitee confronts a known or obvious danger. [***]

    Plaintiffs misunderstand the Court of Appeals’ holding. The Court of Appeals concluded that, on the undisputed evidence in this case, there was no causal link between the county’s failure to warn and the injuries that befell plaintiffs. That conclusion is well supported by the evidence that plaintiffs were fully aware of the danger presented by the drop-off and the lack of a barrier at the edge of the platform.

    In the present case, the evidence on summary judgment establishes that the county’s failure to warn did not expose plaintiffs to any greater risk of harm than if they had been warned. Plaintiffs testified at length at their depositions that they had used the transfer station before, that they knew of and always had been concerned about the drop-off and the lack of a protective barrier at the edge of the platform, and that they had discussed the importance of being careful not to fall. Given that testimony, no reasonable juror could find that a warning would have made a difference. The Court of Appeals was correct in so holding.

    The decision of the Court of Appeals and the judgment of the circuit court are affirmed.

    Note 1. This case also featured two additional important issues: first, the question of the government’s qualified immunity from suit here (to which Module 4 returns, using this same case), and second, the question of whether the transfer station was negligently designed. Can you see the significance of those questions looming in the background, in addition to this more straightforward doctrinal issue of causation?

    Note 2. What was the act or acts that constituted a potential breach of duty here? Why did this not matter? Did the court’s reasoning rest on the plaintiff’s conduct or the defendant’s (or both)?

    Note 3. If the plaintiff had been clearly negligent in his conduct, how might the analysis need to shift? When “but-for causation” fails because of multiple sources of negligent conduct, many courts apply the substantial factor test in which they ask whether the unreasonable conduct was a substantial factor in the ultimate harm. This test has been critiqued because of its malleability since “substantial,” like “reasonable” is a standard that lacks a fixed meaning. However but it can be useful when the causal nexus is complicated.

    Challenges for Causation Analysis

    It is not uncommon in accidents caused by allegedly tortious conduct to find that multiple factors played a role in causing the harm. In some instances, as you will see in the cases throughout this section, it can be proven that either one or another factor (or party) caused the harm but it may remain difficult for the plaintiff to determine which of the two alternate possible tortfeasors was the actual tortfeasor. Such a scenario invites the application of alternate liability, as in Summers v. Tice. However, even more commonly, there are more than two parties or factors potentially to blame. If the factors must havecombined to cause the harm, then under concurrent liability it may be that all are blameworthy whether or not they are all reachable through a lawsuit. (Sometimes, one party is immune or judgment proof or unavailable for some other reason.) Joint and several liability may also apply in some cases.

    Under joint and several liability, any of the tortfeasors may be individually liable for the amount they alone caused or for the amount of harm caused by the whole group, either because the actors were acting in concert (on some sort of outing or joint venture perhaps) or because they caused harm that is effectively indivisible. These are problems of liability—who caused the harm—but also problems of allocation—who should pay for the harm regardless of who actually caused it. In some rare instances, there are numerous separate entities causing wrongdoing and sometimes it is not clear which tortfeasor caused the specific harm suffered by a particular plaintiff. In concert liability fails because the entities are not connected; joint liability fails for the same reason. Alternate liability would also fail because there are more than two. In response to a case of widespread harm in the form of birth defects caused by a drug ingested by pregnant women, the California Supreme Court applied a new doctrine, market share liability, which allows a plaintiff who suffers from some defective product to pursue a manufacturer of the product even if it’s unclear whether that manufacturer or another one caused their harm. There are particular limits as different courts have adopted the doctrine and it is extremely rare for courts to apply it for reasons explained in a later case. In Smith v. Cutter Biological 72 Haw. 416 (1991), the court declined to adopt either alternate liability or joint liability when the hemophiliac recipient of a blood transfusion contracted AIDS from the procedure, but the court found that the plaintiff could recover under market share liability.

    Alternate Liability

    (33 Cal.2d 80)

    Each of the two defendants appeals from a judgment against them in an action for personal injuries. Pursuant to stipulation the appeals have been consolidated. Plaintiff’s action was against both defendants for an injury to his right eye and face as the result of being struck by bird shot discharged from a shotgun. The case was tried by the court without a jury and the court found that on November 20, 1945, plaintiff and the two defendants were hunting quail on the open range. Each of the defendants was armed with a 12 gauge shotgun loaded with shells containing 7 1/2 size shot. Prior to going hunting plaintiff discussed the hunting procedure with defendants, indicating that they were to exercise care when shooting and to ‘keep in line.’ In the course of hunting plaintiff proceeded up a hill, thus placing the hunters at the points of a triangle. The view of defendants with reference to plaintiff was unobstructed and they knew his location. Defendant Tice flushed a quail which rose in flight to a ten foot elevation and flew between plaintiff and defendants. Both defendants shot at the quail, shooting in plaintiff’s direction. At that time defendants were 75 yards from plaintiff. One shot struck plaintiff in his eye and another in his upper lip. Finally it was found by the court that as *83 the direct result of the shooting by defendants the shots struck plaintiff as above mentioned and that defendants were negligent in so shooting and plaintiff was not contributorily negligent.

    First, on the subject of negligence, defendant Simonson contends that the evidence is insufficient to sustain the finding on that score, but he does not point out wherein it is lacking. There is evidence that both defendants, at about the same time or one immediately after the other, shot at a quail and in so doing shot toward plaintiff who was uphill from them, and that they knew his location. That is sufficient from which the trial court could conclude that they acted with respect to plaintiff other than as persons of ordinary prudence. The issue was one of fact for the trial court. [c]

    Defendant Tice states in his opening brief, ‘we have decided not to argue the insufficiency of negligence on the part of defendant Tice.’ It is true he states in his answer to plaintiff’s petition for a hearing in this court that he did not concede this point but he does not argue it. Nothing more need be said on the subject.

    Defendant Simonson urges that plaintiff was guilty of contributory negligence and assumed the risk as a matter of law. He cites no authority for the proposition that by going on a hunting party the various hunters assume the risk of negligence on the part of their companions. Such a tenet is not reasonable. It is true that plaintiff suggested that they all ‘stay in line,’ presumably abreast, while hunting, and he went uphill at somewhat of a right angle to the hunting line, but he also cautioned that they use care, and defendants knew plaintiff’s position. We hold, therefore, that the trial court was justified in finding that he did not assume the risk or act other than as a person of ordinary prudence under the circumstances. [***] None of the cases cited by Simonson are in point.

    The problem presented in this case is whether the judgment against both defendants may stand. It is argued by defendants that they are not joint tortfeasors, and thus jointly and severally liable, as they were not acting in concert, and that there is not sufficient evidence to show which defendant was guilty of the negligence which caused the injuries the shooting by Tice or that by Simonson. Tice argues that there is *84 evidence to show that the shot which struck plaintiff came from Simonson’s gun because of admissions allegedly made by him to third persons and no evidence that they came from his gun. Further in connection with the latter contention, the court failed to find on plaintiff’s allegation in his complaint that he did not know which one was at fault did not find which defendant was guilty of the negligence which caused the injuries to plaintiff.

    Considering the last argument first, we believe it is clear that the court sufficiently found on the issue that defendants were jointly liable and that thus the negligence of both was the cause of the injury or to that legal effect. It found that both defendants were negligent and ‘That as a direct and proximate result of the shots fired by defendants, and each of them, a birdshot pellet was caused to and did lodge in plaintiff’s right eye and that another birdshot pellet was caused to and did lodge in plaintiff’s upper lip.’ In so doing the court evidently did not give credence to the admissions of Simonson to third persons that he fired the shots, which it was justified in doing. It thus determined that the negligence of both defendants was the legal cause of the injury or that both were responsible. Implicit in such finding is the assumption that the court was unable to ascertain whether the shots were from the gun of one defendant or the other or one shot from each of them. The one shot that entered plaintiff’s eye was the major factor in assessing damages and that shot could not have come from the gun of both defendants. It was from one or the other only.

    It has been held that where a group of persons are on a hunting party, or otherwise engaged in the use of firearms, and two of them are negligent in firing in the direction of a third person who is injured thereby, both of those so firing are liable for the injury suffered by the third person, although the negligence of only one of them could have caused the injury. …These cases speak of the action of defendants as being in concert as the ground *85 of decision, yet it would seem they are straining that concept and the more reasonable basis appears in Oliver v. Miles, supra. There two persons were hunting together. Both shot at some partridges and in so doing shot across the highway injuring plaintiff who was travelling on it. The court stated they were acting in concert and thus both were liable. The court then stated (110 So. 668): ‘We think that * * * each is liable for the resulting injury to the boy, although no one can say definitely who actually shot him. To hold otherwise would be to exonerate both from liability, although each was negligent, and the injury resulted from such negligence.’ (Emphasis added.) 110 So. p. 668.

    It is said in the Restatement: ‘For harm resulting to a third person from the tortious conduct of another, a person is liable if he * * * (b) knows that the other’s conduct constitutes a breach of duty and gives substantial assistance or encouragement to the other so to conduct himself, or (c) gives substantial assistance to the other in accomplishing a tortious result and his own conduct, separately considered, constitutes a breach of duty to the third person.’ (Rest., Torts, sec. 876(b)(c).) Under subsection (b) the example is given: ‘A and B are members of a hunting party. Each of them in the presence of the other shoots across a public road at an animal this being negligent as to persons on the road. A hits the animal. B’s bullet strikes C, a traveler on the road. A is liable to C.’ (Rest., Torts, Sec. 876(b), Com., Illus. 3.) An illustration given under subsection (c) is the same as above except the factor of both defendants shooting is missing and joint liability is not imposed. It is further said that: ‘If two forces are actively operating, one because of the actor’s negligence, the other not because of any misconduct on his part, and each of itself sufficient to bring about harm to another, the actor’s negligence may be held by the jury to be a substantial factor in bringing it about.’ (Rest., Torts, sec. 432.)

    Dean Wigmore has this to say: ‘When two or more persons by their acts are possibly the sole cause of a harm, or when two or more acts of the same person are possibly the sole cause, and the plaintiff has introduced evidence that the one of the two persons, or the one of the same person’s two acts, is culpable, then the defendant has the burden of proving that the other person, or his other act, was the sole cause of the harm. (b) * * * The real reason for the rule that each joint tortfeasor is responsible for the whole damage is the practical unfairness of denying the injured person redress simply because he cannot prove how *86 much damage each did, when it is certain that between them they did all; let them be the ones to apportion it among themselves. Since, then, the difficulty of proof is the reason, the rule should apply whenever the harm has plural causes, and not merely when they acted in conscious concert. * * * ’ (Wigmore, Select Cases on the Law of Torts, sec. 153.) Similarly Professor Carpenter has said: ‘(Suppose) the case where A and B independently shoot at C and but one bullet touches C’s body. In such case, such proof as is ordinarily required that either A or B shot C, of course fails. It is suggested that there should be a relaxation of the proof required of the plaintiff * * * where the injury occurs as the result of one where more than one independent force is operating, and it is impossible to determine that the force set in operation by defendant did not in fact constitute a cause of the damage, and where it may have caused the damage, but the plaintiff is unable to establish that it was a cause.’ (20 Cal.L. Rev. 406.)

    When we consider the relative position of the parties and the results that would flow if plaintiff was required to pin the injury on one of the defendants only, a requirement that the burden of proof on that subject be shifted to defendants becomes manifest. They are both wrongdoers both negligent toward plaintiff. They brought about a situation where the negligence of one of them injured the plaintiff, hence it should rest with them each to absolve himself if he can. The injured party has been placed by defendants in the unfair position of pointing to which defendant caused the harm. If one can escape the other may also and plaintiff is remediless. Ordinarily defendants are in a far better position to offer evidence to determine which one caused the injury. This reasoning has recently found favor in this Court. In a quite analogous situation this Court held that a patient injured while unconscious on an operating table in a hospital could hold all or any of the persons who had any connection with the operation even though he could not select the particular acts by the particular person which led to his disability. Ybarra v. Spangard, 25 Cal.2d 486. There the Court was considering whether the patient could avail himself of res ipsa loquitur, rather than where the burden of proof lay, yet the effect of the decision is that plaintiff has made out a case when he has produced evidence which gives rise to an inference of negligence which was the proximate cause of the injury. It is up to *87 defendants to explain the cause of the injury. It was there said: ‘If the doctrine is to continue to serve a useful purpose, we should not forget that ‘the particular force and justice of the rule, regarded as a presumption throwing upon the party charged the duty of producing evidence, consists in the circumstance that the chief evidence of the true cause, whether culpable or innocent, is practically accessible to him but inaccessible to the injured person.’’ 25 Cal.2d at page 490. Similarly in the instant case plaintiff is not able to establish which of defendants caused his injury. [***]

    Cases are cited for the proposition that where two or more tortfeasors acting independently of each other cause an injury to plaintiff, they are not joint tortfeasors and plaintiff must establish the portion of the damage caused by each, even though it is impossible to prove the portion of the injury caused by each. [cc] In view of the foregoing discussion it is apparent that defendants in cases like the present one may be treated as liable on the same basis as joint tortfeasors, and hence the last cited cases are distinguishable inasmuch as they involve independent tortfeasors.

    In addition to that, however, it should be pointed out that the same reasons of policy and justice shift the burden to each of defendants to absolve himself if he can relieving the wronged person of the duty of apportioning the injury to a particular defendant, apply here where we are concerned with whether plaintiff is required to supply evidence for the apportionment of damages. If defendants are independent tortfeasors and thus each liable for the damage caused by him alone, and, at least, where the matter of apportionment is incapable of proof, the innocent wronged party should not be deprived of his right to redress. The wrongdoers should be left to work out between themselves any apportionment. [c] Some of the cited cases refer to the difficulty of apportioning the burden of damages between the independent tortfeasors, and say that where factually a correct division cannot be made, the trier of fact may make it the best it can, which would be more or less a guess, stressing the factor that the wrongdoers are not a position to complain of uncertainty. [c]

    It is urged that plaintiff now has changed the theory of his case in claiming a concert of action; that he did not plead or prove such concert. From what has been said it is clear that there has been no change in theory. The joint liability, as well as the lack of knowledge as to which defendant was liable, was pleaded and the proof developed the case under either theory. We have seen that for the reasons of policy discussed herein, the case is based upon the legal proposition that, under the circumstances here presented, each defendant is liable for the whole damage whether they are deemed to be acting in concert or independently.

    The judgment is affirmed.

    Note 1. Why does the court not discuss whether the parties breached their duty of due care?

    Note 2.Summers v. Tice laid down a rule known now as “alternative liability” to cure the problem created when two defendants are found to have breached their duty, but it is unknown which of them caused the plaintiff’s harm. Do you follow the court’s discussion of in concert liability? And joint liability? Alternative liability differs from “in concert” liability. Can you identify how it does so? Does alternative liability rule seem fair to you? Why or why not? Does it seem efficient, whether or not it seems fair?

    Note 3. The court mentions the problem of “more than one independent force is operating,” which may make it difficult to establish cause and quotes approvingly an article stating that in such cases “there should be a relaxation of the proof required of the plaintiff.” What does it mean, precisely, to “relax” the proof required? Did Ybarra v. Spangard, supra “relax” the proof for the plaintiff? If so, was it in a similar fashion as in Summers? If not, how would you characterize the application of RIL in Ybarra?

    Note 4. If the facts of Summers changed to include multiple hunters, would this change your analysis?

    Note 5.Multiple Sufficient Acts / Overdetermined Causation. In rare instances, more than one act or factor could independently cause a plaintiff’s injuries. The paradigmatic example is fire. Imagine two defendants separately and negligently cause fires to start on either side of the plaintiff’s home and the home is destroyed. Such a scenario would, under the but-for causation test, produce an unfair result: “But for Defendant 1’s negligent conduct, would the plaintiff’s harm still have occurred?” The answer must be yes, since Defendant 2’s conduct would also have resulted in destroying the home. In some cases, forensic analysis or a timeline can provide clues as to which party was more at fault, but in cases of indivisible harm that is occasionally impossible. It would be unfair to allow both parties to escape liability on the grounds that they each could point to the other as also being liable. This is different from Summers v. Tice in which one or the other but not both were liable. Hence a rule evolved to treat both their actions as a cause.

    The Restatement (Third) of Torts: Phys. & Emot. Harm § 27 (2010) provides: “If multiple acts occur, each of which under § 26 alone would have been a factual cause of the physical harm at the same time in the absence of the other act(s), each act is regarded as a factual cause of the harm.”

    Be sure to distinguish a scenario featuring successive tortfeasors from a multiple sufficient causes scenario. Imagine Defendant 1’s tortious conduct causes a collision that kills a plaintiff, if a second negligent ambulance driver comes, correctly confirms the plaintiff is dead and then does some additional minor damage to the plaintiff’s body in transporting it to a morgue. The ambulance driver might be liable for the additional minor damage to the corpse under a wrongful death statute. But they are a successive tortfeasor if so, not a cause of the plaintiff’s death; that liability falls to Defendant 1.

    Negligence: Causation (Issues of Proof)

    (140 F.3d 381)

    [***] This suit under the Federal Tort Claims Act, 28 U.S.C. §§ 1346(b), 2671–2680, was originally filed by Patricia Zuchowicz, who claimed to have developed primary pulmonary hypertension, a fatal lung condition, as a result of the defendant’s negligence in prescribing an overdose of the drug Danocrine. Following Mrs. Zuchowicz’s death in 1991, her husband, Steven, continued the case on behalf of his wife’s estate, claiming that the defendant was responsible for her death. After a bench trial, the district court awarded the plaintiff $1,034,236.02 in damages.

    The case statement recited above goes to the heart of the law of torts. A plaintiff claims to have developed a fatal condition as a result of a defendant’s negligence in prescribing an excessive amount of a drug—a tragic injury allegedly caused by defendant’s wrong. There is no doubt in the case before us either as to the injury or as to the defendant’s wrong; both are conceded. The only issue is causation. Did the action for which the defendant is responsible cause, in a legal sense, the harm which the plaintiff suffered?—a question easily put and often very hard to answer. There is, moreover, no older requirement in this area of law than the need to show such a link between the defendant’s actions and the plaintiff’s loss. It long precedes the obligation to show that the defendant was at fault.[2] Along with the showing of injury, *384 causation constituted an essential part of what the plaintiff had to demonstrate for the early common law action in trespass to lie.[3]

    Over the centuries the courts have struggled to give meaning to this requirement—in the simplest of situations, who hit whom, [fn] and in the most complex ones, which polluter’s emissions, if any, hurt which plaintiff.[4] It is the question that we must seek to answer today in the context of modern medicine and a very rare disease.

    II. Background

    The facts, as determined by the district court, are as follows. On February 18, 1989, Mrs. Zuchowicz filled a prescription for the drug Danocrine at the Naval Hospital pharmacy in Groton, Connecticut. The prescription erroneously instructed her to take 1600 milligrams of Danocrine per day, or twice the maximum recommended dosage. The defendant has stipulated that its doctors and/or pharmacists were negligent and violated the prevailing standard of medical care by prescribing this wrong dosage. [***] In October 1989, she was diagnosed with primary pulmonary hypertension (“PPH”), a rare and fatal disease in which increased pressure in an individual’s pulmonary artery causes severe strain on the right side of the heart. At the time she was diagnosed with the disease, the median life expectancy for PPH sufferers was 2.5 years. [***] PPH is very rare. A National Institute of Health registry recorded only 197 cases of PPH from the mid–1980s until 1992. It occurs predominantly in young women. Exogenous agents known to be capable of causing PPH include birth control pills, some appetite suppressants, chemotherapy drugs, rapeseed oil, and L–Tryptophan. [***]

    Danocrine has been extensively studied and prescribed since the late 1960s for endometriosis. According to the testimony of plaintiff’s expert Dr. W. Paul D’Mowski, who personally performed much of the initial research on the drug, Danocrine is safe and effective when administered properly. Based on studies by Dr. D’Mowski and others, Danocrine was approved by the Food and Drug Administration (“FDA”) for use in dosages not to exceed 800 mg/day. Mrs. Zuchowicz was accidentally given a prescription instructing her to take twice this amount—1600 mg/day. According to Dr. D’Mowski no formal studies of the effects of Danocrine at such high doses have been performed, and very, very few women have received doses this high in any setting.

    The rarity of PPH, combined with the fact that so few human beings have ever received such a high dose of Danocrine, obviously impacted on the manner in which the plaintiff could prove causation. The number of persons who received this type of overdose was simply too small for the plaintiff to be able to provide epidemiological, or even anecdotal, evidence linking PPH to Danocrine overdoses. The plaintiff (Mrs. Zuchowicz’s husband and executor), therefore, based his case primarily on the testimony of two expert witnesses, Dr. Richard Matthay, a physician and expert in pulmonary diseases, and Dr. Randall Tackett, a professor of pharmacology who has published widely in the field of the effects of drugs on vascular tissues. In rendering a judgment for the plaintiff, the district court relied heavily on the evidence submitted by these two experts. The defendant challenges both the admissibility and the sufficiency of their testimony.

    Dr. Richard Matthay is a full professor of medicine at Yale and Associate Director and Training Director of Yale’s Pulmonary and Critical Care Section. He is a nationally recognized expert in the field of pulmonary medicine, with extensive experience in the area of drug-induced pulmonary diseases. Dr. Matthay examined and treated Mrs. Zuchowicz. His examination included taking a detailed history of the progression of her disease, her medical history, and the timing of her Danocrine overdose and the onset of her symptoms. Dr. Matthay testified that he was confident to a reasonable medical certainty that the Danocrine caused Mrs. Zuchowicz’s PPH. When pressed, he added that he believed the overdose of Danocrine to have been responsible for the disease. His conclusion was based on the temporal relationship between the overdose and the start of the disease and the differential etiology method of excluding other possible causes. While Dr. Matthay did not rule out all other possible causes of pulmonary hypertension, he did exclude all the causes of secondary pulmonary hypertension. On the basis of Mrs. Zuchowicz’s history, he also ruled out all previously known drug-related causes of primary pulmonary hypertension.

    Dr. Matthay further testified that the progression and timing of Mrs. Zuchowicz’s disease in relation to her overdose supported a finding of drug-induced PPH. Dr. Matthay emphasized that, prior to the overdose, Mrs. Zuchowicz was a healthy, active young woman with no history of cardiovascular problems, and that, shortly after the overdose, she began experiencing symptoms of PPH such as weight gain, swelling of hands and feet, fatigue, and shortness of breath. He described the similarities between the course of Mrs. Zuchowicz’s illness and that of accepted cases of drug-induced PPH, and he went on to discuss cases involving classes of drugs that are known to cause other pulmonary diseases (mainly anti-cancer drugs). He noted that the onset of these diseases, which are recognized to be caused by the particular drugs, was very similar in timing *386 and course to the development of Mrs. Zuchowicz’s illness.

    Dr. Randall Tackett is a tenured, full professor of pharmacology and former department chair from the University of Georgia. He has published widely in the field of the effects of drugs on vascular tissues. Dr. Tackett testified that, to a reasonable degree of scientific certainty, he believed that the overdose of Danocrine, more likely than not, caused PPH in the plaintiff by producing: 1) a decrease in estrogen; 2) hyperinsulinemia, in which abnormally high levels of insulin circulate in the body; and 3) increases in free testosterone and progesterone. Dr. Tackett testified that these hormonal factors, taken together, likely caused a dysfunction of the endothelium leading to PPH. Dr. Tackett relied on a variety of published and unpublished studies that indicated that these hormones could cause endothelial dysfunction and an imbalance of vasoconstrictor effects.

    II. Discussion

    A. Was the Admission of the Plaintiff’s Experts’ Testimony Manifestly Erroneous?

    The defendant’s first argument is that the district court erred in admitting the testimony of Dr. Tackett and Dr. Matthay. We review the district court’s decision to admit or exclude expert testimony under a highly deferential abuse of discretion standard. [c] The Federal Rules of Evidence permit opinion testimony by experts when the witness is “qualified as an expert by knowledge, skill, experience, training, or education,” and “[i]f scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue.” Fed.R.Evid. 702. And though in Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 588–89, (1993), the Supreme Court altered the traditional test for the admissibility of expert testimony, it did not change the standard of appellate review of these decisions [c].[5]

    Under Daubert, trial judges are charged with ensuring that expert testimony “both rests on a reliable foundation and is relevant to the task at hand.” 509 U.S. at 597. Thus, while Daubert and the Federal Rules of Evidence “allow district courts to admit a somewhat broader range of scientific testimony than would have been admissible under Frye, they leave in place the ‘gatekeeper’ role of the trial judge in screening such evidence.” [c] Indeed Daubert strengthens this role, for it requires that judges make a “preliminary assessment of whether the reasoning or methodology underlying the testimony is scientifically valid and of whether that reasoning or methodology properly can be applied to the facts in issue.” 509 U.S. at 592–93.

    The factors identified by the Supreme Court as relevant to this inquiry are: (1) whether the theory can be (and has been) tested according to the scientific method; (2) whether the theory or technique has been subjected to peer review and publication; (3) in the case of a particular scientific technique, the known or potential rate of error; and (4) whether the theory is generally accepted. See id. at 593–94. The Court emphasized, however, that these factors were not an exclusive or dispositive list of what should be considered, and *387 that the trial court’s inquiry should be a “flexible one.” Id. at 594.

    The question in this case is whether, in light of these factors, the district court’s decision to admit the testimony of Dr. Matthay and Dr. Tackett was an abuse of discretion. [***] In the case before us [***] the district court carefully undertook and fulfilled its role in making the evaluation required by Daubert—a “preliminary assessment of whether the reasoning or methodology underlying the testimony is scientifically valid and of whether that reasoning or methodology properly can be applied to the facts in issue.” 509 U.S. at 592–93. Where, as in this case, the district court decides to admit the testimony of well-credentialed experts relying on scientific methodology, we should and will be reluctant to upset that decision as an abuse of discretion.

    In the district court, the defendant made substantially the same arguments, regarding the validity of the methods used by Dr. Matthay and Dr. Tackett in reaching their conclusions, that it now raises on appeal. The district court rejected these arguments, stating that the plaintiff’s experts “based their opinions on methods reasonably relied on by experts in their particular fields.” We do not believe that the district court’s decision in this regard was erroneous, let alone manifestly so.

    B. Were the District Cour t’s Factual Findings with Respect to Causation Clearly Erroneous?

    We review the district court’s factual findings for clear error. [c] The defendant argues that, even assuming that the testimony of the plaintiff’s experts was admissible, the district court’s finding that the Danocrine overdose more likely than not caused Mrs. Zuchowicz’s illness was clearly erroneous. The defendant contends that, since Danocrine has never been previously linked to PPH, the district court’s conclusion that the drug caused Mrs. Zuchowicz’s illness was impermissible. For the reasons stated below, we reject the defendant’s arguments.

    The liability of the federal government under the Federal Tort Claims Act is determined according to the law of the state in which the injury occurred. See 28 U.S.C. § 1346(b); [c] Connecticut law, therefore, provides the applicable standards in this case. A plaintiff alleging medical malpractice in Connecticut must first prove that the defendant negligently deviated from the customary standard of care. [c] Since the defendant has stipulated that its agents were negligent in prescribing an overdose of the drug Danocrine, there is no question that this requirement is satisfied. In addition, “the plaintiff must establish a causal relationship between the physician’s negligent actions or failure to act and the resulting injury by showing that the action or omission constituted a substantial factor in *388 producing the injury.” [cc] This “substantial factor” causation requirement is the crux of the case before us.

    To meet the requirement that defendant’s behavior was a substantial factor in bringing about the plaintiff’s injury, the plaintiff must generally show: (a) that the defendant’s negligent act or omission was a but for cause of the injury,[6] (b) that the negligence was causally linked to the harm, [fn] and (c) that the defendant’s negligent act or omission was proximate to the resulting injury. *389 [fn] [***]

    In the case before us, as we shall see, neither the requirement of proximity nor that of causal link gives rise to any problems (though the presence of a strong causal link will prove to be highly significant). The case turns only on the difficulty of showing a but for cause. On whether, in other words, the plaintiff has sufficiently demonstrated: (a) that defendant’s act in giving Mrs. Zuchowicz Danocrine was the source of her illness and death, and (b) that it was not just the Danocrine, but its negligent overdose that led to Mrs. Zuchowicz’s demise.

    We hold that, on the basis of Dr. Matthay’s testimony alone, the finder of fact *390 could have concluded—under Connecticut law—that Mrs. Zuchowicz’s PPH was, more likely than not, caused by Danocrine. While it was not possible to eliminate all other possible causes of pulmonary hypertension, the evidence presented showed that the experts had not only excluded all causes of secondary pulmonary hypertension, but had also ruled out all the previously known drug-related causes of PPH. In addition, [***] that the progression and timing of Mrs. Zuchowicz’s illness in relationship to the timing of her overdose supported a finding of drug-induced PPH to a reasonable medical certainty. In this respect, we note that in the case before us, unlike many toxic torts situations, there was not a long latency period between the onset of symptoms and the patient’s exposure to the drug that was alleged to have caused the illness. Rather, [***] the plaintiff began exhibiting symptoms typical of drug-induced PPH shortly after she started taking the Danocrine. Under the circumstances, we cannot say that the fact finder was clearly erroneous in determining that, more probably than not, the Danocrine caused Mrs. Zuchowicz’s illness.

    To say that Danocrine caused Mrs. Zuchowicz’s injuries is only half the story, however. In order for the causation requirement to be met, a trier of fact must be able to determine, by a preponderance of the evidence, that the defendant’s negligence was responsible for the injury. In this case, defendant’s negligence consisted in prescribing an overdose of Danocrine to Mrs. Zuchowicz. For liability to exist, therefore, it is necessary that the fact finder be able to conclude, more probably than not, that the overdose was the cause of Mrs. Zuchowicz’s illness and ultimate death. The mere fact that the exposure to Danocrine was likely responsible for the disease does not suffice.

    The problem of linking defendant’s negligence to the harm that occurred is one that many courts have addressed in the past. A car is speeding and an accident occurs. That the car was involved and was a cause of the crash is readily shown. The accident, moreover, is of the sort that rules prohibiting speeding are designed to prevent. But is this enough to support a finding of fact, in the individual case, that speeding was, in fact, more probably than not, the cause of the accident? The same question can be asked when a car that was driving in violation of a minimum speed requirement on a super-highway is rear-ended. Again, it is clear that the car and its driver were causes of the accident. And the accident is of the sort that minimum speeding rules are designed to prevent. But can a fact finder conclude, without more, that the driver’s negligence in driving too slowly led to the crash? To put it more precisely—the defendant’s negligence was strongly causally linked to the accident, and the defendant was undoubtedly a but for cause of the harm, but does this suffice to allow a fact finder to say that the defendant’s negligence was a but for cause?

    At one time, courts were reluctant to say in such circumstances that the wrong could be deemed to be the cause. They emphasized the logical fallacy of post hoc, ergo propter hoc, and demanded some direct evidence connecting the defendant’s wrongdoing to the harm. See, e.g., Wolf v. Kaufmann, 227 A.D. 281, 282 (1929) (denying recovery for death of plaintiff’s decedent, who was found unconscious at foot of stairway which, in violation of a statute, was unlighted, because the plaintiff had offered no proof of “any causal connection between the accident and the absence of light”).

    All that has changed, however. And, as is so frequently the case in tort law, Chief Judge Cardozo in New York and Chief Justice Traynor in California led the way. In various opinions, they stated that: if (a) a negligent act was deemed wrongful because that act increased the chances that a particular type of accident would occur, and (b) a mishap of that very sort did happen, this was enough to support a finding by the trier of fact that the negligent behavior caused the harm. Where such a strong causal link exists, it is up to the negligent party to bring in evidence denying but for cause and suggesting *391 that in the actual case the wrongful conduct had not been a substantial factor.

    Thus, in a case involving a nighttime collision between vehicles, one of which did not have the required lights, Judge Cardozo stated that lights were mandated precisely to reduce the risk of such accidents occurring and that this fact sufficed to show causation unless the negligent party demonstrated, for example, that in the particular instance the presence of very bright street lights or of a full moon rendered the lack of lights on the vehicle an unlikely cause. See Martin v. Herzog, 228 N.Y. 164 (1920); see also Clark v. Gibbons, 66 Cal.2d 399 (1967) (Traynor, C.J., concurring in part and dissenting in part on other grounds).

    The general acceptance of this view is both signaled and explained by Prosser, which states categorically:

    And whether the defendant’s negligence consists of the violation of some statutory safety regulation, or the breach of a plain common law duty of care, the court can scarcely overlook the fact that the injury which has in fact occurred is precisely the sort of thing that proper care on the part of the defendant would be intended to prevent, and accordingly allow a certain liberality to the jury in drawing its conclusion.

    Prosser, supra note 6, § 41, at 270; see also Calabresi, supra note 6, at 71–73.

    It is clear that Connecticut accepts this approach. [***] The case before us is a good example of the above-mentioned principles in their classic form. The reason the FDA does not approve the prescription of new drugs at above the dosages as to which extensive tests have been performed is because all drugs involve risks of untoward side effects in those who take them. Moreover, it is often true that the higher the dosage the greater is the likelihood of such negative effects. At the approved dosages, the benefits of the particular drug have presumably been deemed worth the risks it entails. At greater than approved dosages, not only do the risks of tragic side effects (known and unknown) increase, but there is no basis on the testing that has been performed for supposing that the drug’s benefits outweigh these increased risks. See generally 21 U.S.C. § 355(d) (indicating that the FDA should refuse to approve a new drug unless the clinical tests show that the drug is safe and effective for use under the conditions “prescribed, recommended, or suggested in the proposed labeling”). It follows that when a negative side effect is demonstrated to be the result of a drug, and the drug was wrongly prescribed in an unapproved and excessive dosage (i.e. a strong causal link has been shown), the plaintiff who is injured has generally shown enough to permit the finder of fact to conclude that the excessive dosage was a substantial factor in producing the harm.

    In fact, plaintiff’s showing in the case before us, while relying on the above stated principles, is stronger. For plaintiff introduced some direct evidence of causation as well. On the basis of his long experience with drug-induced pulmonary diseases, one of plaintiff’s experts, Dr. Matthay, testified that the timing of Mrs. Zuchowicz’s illness led him to conclude that the overdose (and not merely Danocrine) was responsible for her catastrophic reaction.

    Under the circumstances, we hold that defendant’s attack on the district court’s finding of causation is meritless.

    Note 1. Why was it a challenge for the plaintiff to establish causation? The court offers reasoning that suggests the facts of this case made it especially difficult. When do you imagine it is not difficult to prove causation in cases involving pharmaceutical drugs and other complex chemicals? What level of certainty should be required in assessing causation in humans if no human trials have been conducted?

    Note 2. What role does negligence per se play in this case?

    Note 3.Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993).Zuchowicz refers to Daubert, a case that reformed the standards by which scientific testimony could be admitted in federal courts. Post-Daubert, testimony must be both relevant (under the Federal Rules of Evidence) and reliable (using a new list of factors cited in the opinion above) before it may be admissible. You will likely learn about Daubert (pronounced DOW (rhymes with cow)-burt) when you study Evidence (in law school or for the bar exam), and it’s an important case for tort law’s breach, causation and damages inquiries. What you need to know for tort law is that it’s the applicable standard for scientific and medical evidence in federal courts. Some state courts have also adopted Daubert while others retained Frye, the older standard, which required that expert testimony be subject to “generally accepted principles.” Frye v. United States, 293 F. 1013, 1014 (D.C. Cir. 1923).

    Implications for Social Justice

    (184 Misc.2d 639)

    Defendant City of New York moves, and co-defendants, 1845 7th Avenue Realty Associates, L.P., 1845 7th Avenue, Inc., Ari Parnes and Sharp Management Corp., cross-move, for an order compelling plaintiffs to provide authorizations for the siblings’ complete school records, including colleges or universities attended, courses taken and grades received, teacher reports and evaluations, and the results of standardized tests, SAT and Advanced Placement tests, and psychological testing and evaluations. Alternatively, defendants move and cross-move for an order precluding plaintiffs from offering any evidence at trial regarding the academic performance of the infant plaintiff’s siblings. Plaintiffs oppose the motion and cross-motion.

    This is an action for damages for personal injuries sustained by the infant plaintiff, Jordan Nieves, born on September 5, 1992, as the result of exposure to lead-based paint while residing at 1851 7th Avenue, Apt. 15, New York, New York. In May 1997, defendant City served a Demand for Discovery and Inspection requesting, inter alia, the name, date of birth and current address of any siblings of the infant plaintiff, and for each sibling, the “[n]ames and addresses of any and all schools, pre-schools or day-care centers attended, and duly executed authorizations allowing those institutions to release their records to the defendant(s).” Plaintiffs responded with the names and dates of birth of three siblings (Kevin Michael Cleare, DOB 1/9/81; David Christopher Nieves, DOB 2/16/81; and Ishmael Cleare, DOB 10/3/83), but objected to the demand for academic information as “seek[ing] irrelevant and private information.” In August 1998, co-defendants served a Demand for Authorizations to obtain the complete educational records of the infant plaintiff’s siblings, to which plaintiffs’ counsel objected.

    In May 1999, plaintiffs served their Response for Expert Information, which identified Dr. Leon I. Charash, M.D., a pediatric neurologist, as their expert witness, and annexed his April 6, 1999 report. In that report, Dr. Charash concludes that Jordan Nieves

    is behind academically and has been tested as having problems with processing of information and problems with attention deficit disorder. These are all evident on today’s examination. Within reasonable certainty his lead poisoning is causally responsible for these problems and has *641 significantly impacted upon his intelligence and his ability to achieve academically as well as his problems with coordination and speech. Finally, of course, his attention deficit problems are additionally viewed as being related to his plumbism [plumbism is the technical term for lead poisoning]. Of special interest is the fact that he has three older siblings, one of whom entered UCLA having finished high school a year earlier than normal. Another brother has done well at school and is planning to go onto college and to study law if possible. His sixteen year old brother is also doing well. There is some indication that all three of these boys have been variably placed in gifted programs through their school careers.

    In support of this motion to compel or preclude, defendants contend that they are entitled to discovery regarding the siblings’ academic performance, because it bears directly on a significant issue raised by plaintiffs. Defendants assert that plaintiffs now intend to use the very evidence they deemed irrelevant and refused to give discovery on two years ago, to support their own claim that Jordan would have gone to college if he had not been exposed to lead paint. According to counsel for defendant City, when the parties appeared for a compliance conference before this Court on June 4, 1999, “plaintiffs’ attorney admitted that plaintiffs would claim at trial that Jordan would have attended college but for his lead poisoning, and intended to offer fact and expert evidence regarding how Jordan’s siblings had done academically.” Defendants argue that if plaintiffs are permitted to offer evidence as to the successful academic performance of Jordan’s brothers, defendants are entitled to the brothers’ school records, so that they will be in a position to refute plaintiffs’ claim and to cross-examine Dr. Charash and any other witnesses testifying as to this issue. Alternatively, defendants argue that if plaintiffs do not wish to provide such discovery, they should be precluded from offering any evidence of the brothers’ academic performance.

    In opposition to the motion, plaintiffs assert that the brothers’ school records are not material and relevant to any issue in this action, and that defendants are entitled only to the general factual observations of the infant plaintiff’s mother, who testified at her further deposition as to the specific schools attended by the siblings and the dates of attendance. Plaintiffs assert that Dr. Charash did not examine the siblings’ school records, and the statements in his report are based on the history provided by the infant plaintiff’s father, who made general observations of his children’s academic performance. Alternatively, plaintiffs argue that if the motion to compel is granted, the records should be examined by the Court in camera.

    *642 [***] Defendants’ motion and cross-motion to compel disclosure or to preclude are denied except to the limited extent indicated below. It is undisputed that two siblings, Kevin Cleare and David Nieves, have both reached the age of majority, and, as such, only they, nonparties to this action, can provide the authorizations sought by defendants. [***] As neither Kevin Cleare nor David Nieves was served with the order to show cause or the notice of cross-motion, the Court lacks jurisdiction over them for the purposes of the motion and cross-motion. In any event, even if Kevin Cleare and David Nieves had been properly served, the motion and cross-motion to compel disclosure is hereby denied with respect to the academic records of all three siblings, as defendants’ discovery demand is over broad, and the relevance and materiality of the requested information to any claim or defense in the action has not been established. [cc] See Andon v. 302–304 Mott Street Assocs., 94 N.Y.2d 740; Monica W. v. Milevoi, 252 A.D.2d 260, 263 (1st Dept.1999); McGuane v. M.C.A. Inc., 182 A.D.2d 1081 (4th Dept.1992).

    Generally, in the reported decisions on disclosure in lead paint cases, defendants seek intelligence quotient (I.Q.) testing, and medical, academic and employment records of parents and siblings, who are usually non-parties, to dispute the issue of causation, theorizing that the requested information may lead to the discovery of admissible evidence relevant to whether the infant plaintiff’s condition is the result of a genetic disorder or some environmental factor other than lead. See e.g. [cc]; Wepy v. Shen, 175 A.D.2d 124 (2nd Dept.1991); *643Baldwin v. Franklin General Hospital, 151 A.D.2d 532 (2d Dept.1989); Van Epps v. County of Albany, 184 Misc.2d 159 (Sup.Ct., Albany Co.); Espinal v. 570 W. 156th Assocs, N.Y.L.J., December 31, 1998, p. 27, col. 2 (Sup.Ct., N.Y.Co.); Washington v. Bayley Seton Hospital, N.Y.L.J., May 12, 1998, p. 25, col. 5 (Sup.Ct., N.Y.Co.); Anderson v. Seigel, 175 Misc.2d 609 (Sup.Ct., Kings Co.), aff’d as modified, 255 A.D.2d 409 (2nd Dept.1998); Alan C. Eagle & Charlotte Biblow, Courts in Lead Cases Allow Discovery of Siblings’ Academic & IQ Records, N.Y.L.J., April 12, 1999, p. 1, col. 1; Hope Viner Sanborn, Blame It On the Bloodline, Discovery of Non–Parties’ Medical and Psychiatric Records is Latest Defense Tactic in Disputing Causation, 85 A.B.A.J. 28 (Sept.1999); Jennifer Wriggins, Genetics, IQ, Determinism, and Torts: The Example of Discovery in Lead Exposure Litigation, 77 B.U.L. Rev. 1025 (1997).

    In the decisions reported to date, the First Department, Appellate Division and the Second Department, Appellate Division rely on the identical legal principles in analyzing the issues on a case-by-case basis, but have split on the outcomes reached. The First Department so far has denied such disclosure, Andon v. 302–304 Mott Street Assocs., 257 A.D.2d 37 (1st Dept. 1999), aff’d 94 N.Y.2d 740; [cc] and the Second Department has consistently granted it [cc].

    The one opinion by the Court of Appeals rendered recently in Andon v. 302–304 Mott Street Assocs, supra, affirmed the First Department, Appellate Division’s denial of defendants’ motion to compel the plaintiff-mother to submit to an IQ test. Rejecting defendants’ argument that the Appellate Division had created a “blanket prohibition” against discovery of maternal IQ in all lead paint cases, the Court of Appeals found that the Appellate Division had “evaluated defendants’ request in the context of this case and in light of the evidence presented to it. The Appellate Division concluded that the burden of subjecting plaintiff-mother to an IQ test outweighed any relevance her IQ would bear on the issue of causation. The Court noted that the mother’s mental condition is not in dispute and that IQ results, while not confidential, are private. Under these circumstances, we are satisfied that the Appellate Division did not abuse its discretion as a matter of law.” [fn]

    *644 Here, neither plaintiffs nor defendants have made a sufficient showing that the siblings’ academic records are relevant or material to the question of whether the infant plaintiff’s cognitive deficits and emotional behavior problems are causally related to his ingestion of lead paint. The discovery dispute over the siblings’ academic records resurfaced when plaintiffs exchanged the report of their expert neurologist, Dr. Charash. This report includes limited second-hand information about the siblings’ successful academic performance, which Dr. Charash attempts to use as further support for his conclusion that the infant plaintiff’s impairments were caused by exposure to lead paint. However, any claim by plaintiffs, that there is a correlation between the infant plaintiff’s impairments and his siblings’ academic performance, is speculative, at best. [cc] [T]he parties have failed to produce an expert affidavit “to demonstrate that the extent to which the adverse effects of lead exposure contributed to the mental and physical condition of the infant plaintiffs cannot be ascertained by reference to objective clinical criteria and expert testimony.” Supra, at 263, 685 N.Y.S.2d 231.

    Defendants likewise fail to show how the siblings’ academic information pertains to any disability or developmental impairment experienced by the infant plaintiff, as the record contains no indication that the siblings share any of the infant plaintiff’s impairments. [***] To the contrary, Ms. Cleare testified that the siblings Kevin Cleare and Ishmael Cleare were never evaluated for any special education, speech or learning problems, and that they were both in gifted programs at various times.

    Thus, under the circumstances presented, neither proof nor case law provides a basis for concluding that the siblings’ academic records are material and relevant to the issue of causation. However, if at trial, plaintiffs intend to introduce evidence that the siblings attended certain schools or certain programs, plaintiffs shall provide defendants with documentary proof of *645 the siblings’ enrollment at the schools, within 45 days of the date of this order. The court herein makes no determination as to the admissibility of such evidence at trial, which shall be reserved for the trial court.

    [Defendant’s motion and cross-motion denied.]

    Note 1. What did the defendants’ strategy appear to be with respect to the siblings’ academic records it sought? What alternative strategies might be available in light of this motion’s denial?

    Note 2. Would it help the plaintiff on this issue to be able to bring the claim under strict liability rather than negligence? Why or why not?

    Note 3. Would you distinguish between a parent and a sibling’s records, with respect to an infant’s exposure to a toxic environment? Is it possible that toxicity in an environment might manifest in ways that affect both parent and infant, and should that be relevant for the question of causation in fact? To what extent is genetic testing a proxy for other factors and what do you think, normatively, about its utility and appropriateness in cases of long-term injury such as this one?

    Note 4. Should courts considering the use of siblings’ or parents’ educational records to assess causation take into account the way socioeconomic privilege and race have historically determined (and limited) educational and professional opportunities? Are structural problems like systemic inequity in education beyond the scope of tort law?

    Note 5. The court cites numerous cases and articles on the topic of lead paint litigation. In fact the harms posed by lead point are substantial and widespread. Many homes built in the first half of the twentieth century contain lead-based paint, whose use was banned starting in 1978. The lead-based paint may chip, flake or be absorbed into groundwater and dirt and thus be ingested by children in one or many forms. “Studies have linked high lead exposure to decreased fertility, spontaneous abortions, miscarriages, and other pathologies. Studies dating back to 1929 have established especially pernicious consequences of high lead exposure to children including …brain damage and learning disabilities, hyperactivity, and impaired hearing. Such effects are long-term.” Donald E. Lively, The Diminishing Relevance of Rights: Racial Disparities in the Distribution of Lead Exposure Risks, 21 B.C. Envtl. Aff. L. Rev. 309, 314 (1994) (internal citations omitted).

    The Center for Disease Control considers any reading blood-level higher than ten mg/dL, to require intervention. The Secretary of Health and Human Services has described lead poisoning as “the number one environmental threat to the health of children in the United States.” Id. at 316. The toxicity and ubiquity of lead-based paint present a significant public health problem. Yet its impact lands disproportionately among people of color. “[S]ignificant disparities in blood-lead levels exist on the basis of ethnicity. Recent studies have confirmed consistent and significant exposure variances correlated to race. When race and income are factored together disparities are even more egregious. An Agency for Toxic Substances and Disease Registry study disclosed that, among families with an annual income under $6,000, the percentage of black children having blood-lead levels exceeding fifteen mg/dL is sixty-eight percent, contrasted with a level for white children of thirty-six percent. The independent significance of race is further evidenced by results showing that 26.6 percent of all African-American children, as opposed to 7.1 percent of all white children, have blood-lead levels exceeding fifteen mg/dL.” Id. at 317.

    White flight and other demographic changes in cities have contributed to this concentration of higher-risk in lower-income communities. Whatever the other causes, the racial disparity in toxic injury is clear. What is the proper role for tort law, if any, in systematically remedying the wrongs caused by common use of lead-based paints? What is the proper role for the legislature, if any?

    (613 Fed.Appx. 187)

    D.M., a minor (“Plaintiff”), by and through her mother, Ravonnia Ray, appeals *188 the dismissal of her substantive due process claim against the Philadelphia Housing Authority (the “PHA”) for D.M.’s exposure to lead point that occurred while she and Ray lived in Section 8 housing.[7] We will affirm. [***] Sometime before June 1, 2006, the PHA entered into a Housing Assistance Payment (“HAP”) contract with John Cassidy, the owner and landlord of an apartment building in Philadelphia, Pennsylvania (the “Property”), pursuant to the Federal Housing Choice Voucher Program under Section 8 of the United States Housing Act, 42 U.S.C. § 1437, et seq. (the “Section 8 Program”). Cassidy “operated, managed, maintained, [and] controlled” the Property. App. 32A.

    On June 1, 2006, Ray entered into a two-year lease agreement for the Property with Cassidy. The PHA approved Ray’s lease for inclusion in the Section 8 Program and, in accordance with the HAP contract, paid Cassidy $501 per month in subsidies on Ray’s behalf.[8]

    On June 1, 2008, Ray renewed her lease, which the PHA again approved for inclusion in the Section 8 Program. The lease renewal included a “Lead–Based Paint Disclosure Addendum” that was binding on Cassidy. In March 2009, the PHA inspected the Property and discovered several violations of the Section 8 Program’s Housing Quality Standards (“HQS”), including uncovered electrical outlets, broken windows, and inoperable range burners. The PHA re-inspected the Property three times in April and May 2009, and reported that Cassidy failed to address the HQS violations. None of the PHA’s inspection reports identified lead paint-related hazards in the Property.

    On June 25, 2009, D.M. underwent a blood test that revealed “dangerously elevated levels of lead.” Ray sent D.M.’s blood test results to the Philadelphia Department of Health (the “DOH”), which inspected the Property and found lead-based paint on more than eighty surfaces. The DOH ordered Cassidy to eliminate the lead-based paint, but he failed to do so. D.M. and Ray eventually moved out of the Property.

    Plaintiff filed a five-count Complaint against Cassidy and the PHA in connection with D.M.’s lead paint exposure. The District Court granted the PHA’s motion to dismiss under Fed.R.Civ.P. 12(b)(6), holding in pertinent part that Plaintiff’s 42 U.S.C. § 1983 state-created danger claim against the PHA failed to allege that the PHA’s approval of the Property for inclusion in its Section 8 Program was a “fairly direct” cause of D.M.’s injuries. Plaintiff appeals [The District Court dismissed all of Plaintiff’s claims against the PHA, but Plaintiff only appeals its dismissal of her state-created danger claim (Count IV)].

    Plaintiff alleges that the PHA violated her due process rights by “exercis[ing its] authority in a manner” that made her “more vulnerable to danger” from lead-based paint in the Property. “[T]he Due Process Clauses generally confer no affirmative right to governmental aid, even where such aid may be necessary *190 to secure life, liberty, or property interests of which the government itself may not deprive the individual.” DeShaney v. Winnebago Cnty. Dep’t of Soc. Servs., 489 U.S. 189, 196, 109 S.Ct. 998 (1989). A state actor, however, “may be held liable under the ‘state-created danger’ doctrine for creating a danger to an individual in certain circumstances.” Henry v. City of Erie, 728 F.3d 275, 281 (3d Cir.2013) [c]).

    A state-created danger claim has four elements:

    (1) the harm ultimately caused was foreseeable and fairly direct;
    (2) a state actor acted with a degree of culpability that shocks the conscience;
    (3) a relationship between the state and the plaintiff existed such that the plaintiff was a foreseeable victim of the defendant’s acts, or a member of a discrete class of persons subjected to the potential harm brought about by the state’s actions, as opposed to a member of the public in general; and
    (4) a state actor affirmatively used his or her authority in a way that created a danger to the citizen or that rendered the citizen more vulnerable to danger than had the state not acted at all.

    Id. at 282. “To fulfill the ‘fairly direct’ requirement of the state-created danger claim, the plaintiff must plausibly allege that state officials’ actions precipitated or were the catalyst for the harm for which the plaintiff brings suit.” [c] “Precipitate, in turn, means to cause to happen or come to a crisis suddenly, unexpectedly, or too soon.” Id. (internal quotation marks omitted). Thus, for purposes of the fairly direct requirement, it “is insufficient to plead that state officials’ actions took place somewhere along the causal chain that ultimately led to the plaintiff’s harm.” Id. (dismissing § 1983 state-created danger claim for the plaintiffs’ fire-related injuries incurred while living in Section 8 housing because the “defendants’ approval and subsidization of the apartment did not lead ‘fairly directly’ to the fire that claimed the [plaintiffs’] lives”).

    Plaintiff failed to plausibly allege that the PHA precipitated, caused, or was the catalyst for her harm. Plaintiff alleges that the PHA “failed to discover” the lead paint in its March 2009 annual inspection, and “rendered plaintiff[ ] more vulnerable to danger than had [it] not acted at all” by: (1) including the Property in the Section 8 program despite numerous HQS violations; (2) making repeated HAP payments to Cassidy despite the HQS violations; and (3) “[r]equiring” that Plaintiff “remain” at the Property despite the “life-threatening violations of HQS” and lead paint hazards. However, Plaintiff does not allege that the PHA introduced lead paint to the Property or was responsible for its presence there.[9]See Henry, 728 F.3d at 285 (finding no “fairly direct” causation where the plaintiffs “did not allege that [municipal] defendants caused the fire,” “increased the apartment’s susceptibility to fire,” or “failed to install a smoke detector and a fire escape”). Nor does Plaintiff allege that the PHA increased the quantity of lead paint in the Property or “did anything to hinder [Cassidy] from bringing [the Property] into compliance” with HQS. Id. at 285. While the PHA subsidized the Property and was allegedly “aware of the dangers that [Plaintiff] faced …, it played no part in their creation, nor did it do anything to *191 render [Plaintiff] any more vulnerable to them.” DeShaney, 489 U.S. at 201. In short, Plaintiff’s allegations fail to show “that [the PHA] created the danger” Plaintiff faced while living in the Property. Henry, 728 F.3d at 286.[10]

    For the foregoing reasons, we will affirm.

    Note 1. How significant was the fact that the plaintiff signed a lease with a lead discloser addendum, do you think? Have you signed such documents before? Do you read them thoroughly before signing? Have you ever chosen not to go through with signing a document because of discovering a particular term, clause, or disclosure? Regardless of the plaintiff’s awareness of the lead, should it bar her infant daughter’s right of recovery? Why or why not?

    Note 2. The state-created danger doctrine provides a cause of action against a state official that is analogous in several respects to negligence claims against private individuals. Reviewing the 4-pronged test set out above, do you see parallels to duty, breach, causation and damages? Do you see how the plaintiff’s case could be said to have failed due to lack of causation, or her inability to prove it?

    Note 3. Is the causation requirement fatally flawed in the context of chemical or toxic torts? At least one scholar has called for its elimination. Margaret A. Berger, Eliminating General Causation: Notes Towards A New Theory of Justice and Toxic Torts, 97 Colum. L. Rev. 2117, 2145 (1997) Berger points to asbestos litigation as a paradigmatic example and observes that manufacturers knew about its risks and harms long before they were willing to disclose them to the public. This failure to disseminate information in a responsible manner had several negative consequences. It augmented the number of people who suffered from asbestos exposure, contributed to burdening judicial dockets, and ultimately made causation more challenging to establish as well. Id. at 2143. Berger argues that the problem is structural; businesses are incentivized to behave in this way:

    Even when a corporation is well-aware of the risk it is creating, it may gamble that the future costs for compensation and litigation and administrative penalties, offset by insurance and discounted by inflation, will be less than the current cost of adding safety measures, providing information, or paying for more research. Moreover, once the corporation acknowledges the foreseeability of a toxic tort problem, particularly if there are many potential plaintiffs, the price of its stock may drop in anticipation of lawsuits with enormous transaction costs and huge settlement potential. Such a result is, of course, extremely unpalatable, both because corporate managers’ chief obligation is to their current shareholders, and because the increasing use of stock options as a major component of corporate remuneration means that their own compensation may be tied directly to stock performance. The conflict between short-term and long-term consequences puts management into a bind. The uncertainty about the future proof of causation and the time-lag before anything definitive will emerge tip the balance in favor of resolutions that maximize short-term objectives. Id. at 2139-2140.

    Berger proposes conditioning liability in negligence on failure to provide substantial information relating to risk. Instead of the plaintiff’s needing to prove causation, defendants would benefit from a kind of safe harbor. Provided they proved that they had complied with a mandatorily established standard of care, potential defendants would be insulated from liability for injuries caused by exposure to their products. Berger proposes two additional defenses, “as a matter of fairness and as an inducement to conduct future research.” The first would allow defendants to prove that certain adverse health reactions could not plausibly arise from exposure to their product; the second would allow a reduction of damages in cases in which defendants prove that “a particular plaintiff’s injury is attributable or partly attributable to another cause, such as smoking.” Id. at 2144-2145.

    Does Berger’s idea strike the right balance, in your view? Do her additional defenses effectively create a backdoor requirement of causation for certain plaintiffs, in the language referring to injury’s being “attributable to another cause”? Referring to tort law’s various purposes, what arguments support maintaining causation versus eliminating or modifying it?

    Joint and Several Liability

    Joint and several liability is a rule followed in many jurisdictions that allows a plaintiff whose harm was caused by more than one tortfeasor to recover the full amount of their compensation from any single one of the individuals or from them as a group. The benefit of the rule, from the plaintiff’s perspective, is that if one of the tortfeasors is immune to liability, judgment proof, unidentified or otherwise unavailable, the plaintiff can recover that party’s portion from other tortfeasors. Likewise, if there is one party with deep pockets (or a relevant insurance policy), the plaintiff stands a better chance of receiving the compensation tort law would ostensibly award them if the plaintiff can proceed directly against the deep-pocketed party rather than seeking compensation from multiple parties. From the defendants’ perspective, joint and several liability can seem quite unfair because it doesn’t necessarily track the amount of the tortfeasor’s fault. Further, one party may be better or worse able to pay a judgment and yet still find they owe such a payment regardless of their lesser capacity to pay it. Despite its name, “joint and several liability” is a rule of allocation as much as a rule of liability. In some cases, it is used to find liability with respect to a tortfeasor whose involvement cannot be as clearly established as others also involved; in other cases, it is used to reallocate or shift from one defendant to another the obligation to compensate the plaintiff for the injuries caused by a group of defendants’ wrongful conduct. Often, the party who satisfies the judgment will seek contributions or indemnification from the other tortfeasors.

    “Several liability” means a plaintiff whose harm was caused by more than one tortfeasor can proceed against an individual tortfeasor only for the amount that tortfeasor personally owes under the judgment; the plaintiff may not seek the amount of the full judgment against the group from a single plaintiff in the way joint and several liability permits.

    Jurisdictions have arrived at various different rules regarding joint and several liability. It is not uncommon, even in states that retained joint and several liability, to have limited it in certain domains (such as medical malpractice or products liability cases).

    (72 Haw. 416)

    [By certified question from Smith v. Cutter Biological, Inc., 911 F.2d 374 (9th Cir. 1990)]

    [***] Question 3. Would Hawaii allow recovery in this case when the identity of the actual tortfeasor cannot be proven? If Hawaii would allow recovery, what theory (i.e. burden-shifting, enterprise liability, market share or other) would the Hawaii Supreme Court adopt?

    [***] The instant problem is that the plaintiff cannot identify which particular defendant caused his injury. Our consideration of the issues is limited to the facts as stated in this record. Procedurally, this case reached the Ninth Circuit Court on a summary judgment motion. The order granting summary judgment did not rule on duty and breach as to the manufacturers; summary judgment was granted on the basis that plaintiff failed to prove causation. The other elements of negligence, i.e., duty, breach and damages, are not at issue here. We note that at least two courts have determined, in cases similar to the instant action, that there was no breach of duty. Jones v. Miles Laboratories, Inc., 887 F.2d 1576 (11th Cir.1989); McKee v. Cutter Laboratories, Inc., 866 F.2d 219 (6th Cir.1989). However, those cases are distinguishable.[11] We do not render an opinion as to whether appellant here will overcome the obstacles met by plaintiffs in those cases; the duty and breach issue here has not only not been decided, it is not before this court on the certified questions. Therefore, we do not deal with the viability of those questions.

    *421 Our conclusions deal only with this case—as it comes to us. Therefore, on our reading of the record as it stands, the relevant statutes, and the relevant case law, [***] our answer to question three is “yes,” using the alternative market share theory of recovery, as defined herein.[12]

    Appellant is a hemophiliac who has tested HIV-positive with the AIDS virus.[13] He claims that his exposure to the AIDS virus occurred in 1983 or 1984, through injections of the Antihemophilic Factor Concentrate (Factor VIII or AHF). [fn] Factor *422 VIII, as more fully discussed in Part III, is a blood protein which enables the blood to properly coagulate when a hemophiliac suffers a bleeding episode. The original source of the Factor VIII is through blood donors.

    The United States Tripler Army Medical Hospital (U.S.) was appellant’s dispensary for Factor VIII during the period of time in which appellant claims to have been infected. According to appellant, appellee manufacturers [fn] furnished to the U.S., the Factor VIII which was used by appellant. Upon appellant’s first being tested for HIV antibodies in 1986, the results were positive.

    Appellant filed suit against the four appellee manufacturers of Factor VIII for negligence and strict liability.[14] Defendants moved for summary judgment. Despite acknowledging “that this is a case in which it might be reasonable to apply the principles of market *423 share theory of liability,” the district court granted summary judgment in favor of appellees, holding that appellant failed to prove specifically which manufacturer’s product caused his infection. Appellant took the case to the Ninth Circuit, which certified the questions to this court. [***] *425 IV.

    The reason this case is before this court is because the legislature has not fully legislated in the field of torts. When the occasion arises for which there is no specific rule to apply, “we are free to fashion an appropriate rule of law.” Armstrong v. Cione, 69 Haw. 176, 738 P.2d 79 (1987). We must consider what justification there is for deviating from the traditional proof in a negligence case, which, as this court has previously said, includes the factor of causation. See Knodle v. Waikiki Gateway, 69 Haw. 376, 385 (1987).

    Appellees take issue with applying theories which were developed, in a large part, for remedies in the field of diethylstilbestrol (DES) drug litigation and the inherent problems associated with those actions.[fn] Their strongest argument against using these theories *427 is the lack of comparison of DES to Factor VIII as a fungible product. DES was produced by more than 200 different companies, some of which are defunct, but the identical formula was used universally in a highly regulated industry. With Factor VIII, there are only a handful of manufacturers, and although the product is fungible insofar as it can be used interchangeably, it does not have the constant quality of DES. The reason is obvious—the donor source of the plasma is not a constant. Therefore, Factor VIII is only harmful if the donor was infected; DES is inherently harmful. As we see that the lack of screening of donors and failure to warn are the breaches alleged, appellee’s argument for not using DES theories is not convincing. We find consideration of the theories discussed in the DES cases to be helpful, as we strive to find an equitable and fair solution to the case at bar.

    Our initial reference is to the reasoning of the Supreme Court of California, in Sindell v. Abbott Laboratories, 26 Cal.3d 588, cert. denied, 449 U.S. 912 (1980). We subscribe to the policy reasons propounded in Sindell, and discussed infra, for by-passing the identification requirement.

    In addition, we note that tort law is a continually expanding field. As discussed in the American Law Institute Enterprise Responsibility for Personal Injuries—Reporter’s Study (1991) (ALI Study), the field of torts has now expanded to include personal injury actions described in three tiers of actions. I ALI Study 9. These are loosely defined as first, the traditional level which includes accidents where an individual defendant causes harm to a stranger. The second level includes product defects and medical mishaps which include high stakes cases with erratic jury *428 results. Finally, the third tier includes “mass” torts where toxic exposure to many plaintiffs may, many years later, cause cancer or other illness. Id. at 9–10. It is this final tier with which this case deals. It necessitates considering how to fairly deal with the plight of plaintiffs unable to identify, for no fault of their own, the person or entity who should bear the liability for their injury.

    No longer can we apply traditional rules of negligence, such as those used in individual and low level negligence to mass tort cases, especially here, where we are dealing with a pharmaceutical industry that dispenses drugs on a wide scale that could cause massive injuries to the public, and where fungibility makes the strict requirements difficult to meet. The problem calls for adopting new rules of causation, for otherwise innocent plaintiffs would be left without a remedy. We concede that there is a difference of opinion regarding the need for this change. For instance, in regard to DES cases, the Illinois Supreme Court refused to adopt the market share theory of liability, in part because “[a]cceptance of market share liability and the concomitant burden placed on the courts and the parties will imprudently bog down the judiciary in an almost futile endeavor.” Smith v. Eli Lilly & Co., 137 Ill.2d 222, 253 (1990). In addition, that court criticized the fairness of results in apportioning damage when reliable information on all manufacturers might not be available. Id. Part of that reasoning, of course, is based on the fact that the potential number of defendants in DES cases extends into the hundreds. Id. at 254, 148 Ill. Dec. at 36. The numbers here are not nearly so large, and therefore, the harshness of the result, that is, burdening the innocent plaintiff without a remedy, to us seems totally unfair and out of step with current efforts to allow recovery when the proper case is brought.

    The policies in Sindell and Hall convince us that it is appropriate to consider a negligence action where the actual tortfeasor cannot be proven. Therefore, although inherent in the proof of *429 negligence is proof of causation, we believe that this state is amenable to consideration of group theories of liability.

    [***] There are several theories which have evolved in the last several years. The genesis of these theories comes from Sindell v. Abbott Laboratories, 26 Cal.3d 588 (1980). The theories are generally described as: alternative liability, concert of action, enterprise or industry-wide liability, and market share liability. In the evolution of the DES cases, the market share theory has undergone various modifications, to suit the policies and needs of the particular courts.

    A. Alternative Liability

    This theory is epitomized in the well-known case of Summers v. Tice, 33 Cal.2d 80, 199 P.2d 1 (1948). In that case, two hunters negligently shot in the direction of the plaintiff; one of them injured him. Upon deciding that both were wrongdoers and negligent to the plaintiff, the court felt that it was unfair to leave an impossible burden of proof on the plaintiff, and shifted that burden to the defendants to absolve themselves. The rule of Summers v. Tice is included in the Restatement (Second) of Torts (Restatement) as follows:

    Where the conduct of two or more actors is tortious, and it is proved that harm has been caused to the plaintiff by only one of them, but there is uncertainty as to which one has caused it, the burden is upon each such actor to prove that he has not caused the harm.

    *430Restatement § 433B (3) (1965). The comments in the Restatement also suggest that this theory may appropriately be subject to modification at a later time. Id., comment h.

    Two presumptions follow this theory. First, the plaintiff must prove that “all defendants acted tortiously and that the harm resulted from the conduct of one of them.” Sindell, 163 Cal.Rptr. at 139 n. 16, citing Restatement § 433B, comment g. This has been interpreted to mean that the tortious actions must occur simultaneously. Starling v. Seaboard Coast Line R.R., 533 F. Supp. 183, 191 (S.D.Ga.1982) (court considering theories in asbestos related injury). However, another court, in applying the theory in a Factor VIII case, disagreed. Poole v. Alpha Therapeutic, 696 F. Supp. 351, 356 (N.D. Ill.1988).

    Second, all responsible parties must be joined. Sindell, 163 Cal.Rptr. at 139. Typically, this theory is useful in multiple car crash cases, cases of pollution by several defendants, and injury during medical operations where the plaintiff is sedated. Agent Orange Litigation, 597 F. Supp. 740 (E.D.N.Y.1984). Additionally, however, joint and several liability is inherent in the application of alternative liability.

    We choose not to alter the theory to the point that it would be useful on the facts here. Several problems arise which lead us to this decision. First, we look at the various theories of negligence which appellant suggested. One argument is that there was a duty to properly select and screen donors; other arguments follow the same line of reasoning—that the manufacturers should have implemented verified surrogate laboratory tests, or that they should have ceased using plasma from donor centers where the population groups had significant numbers of AIDS incidents. It is obvious that each manufacturer acted at various different times, so the simultaneous requirement of a strict application of the theory *431 fails. Also, although appellant has alleged that manufacturers are “most” of the possible tortfeasors, and the manufacturers have not clearly rebutted that argument, it is still subject to factual proof and findings. Finally, we do not believe that joint and several liability is appropriate under the circumstances of this case. Therefore, this theory cannot be applied here, unless modified, and we choose not to do so based on these facts, as other theories, discussed infra, have already been appropriately modified.

    B. Concert of Action

    This theory derives from the criminal law concept of aiding and abetting. Starling, 533 F. Supp. at 187. See Restatement § 876. Concert of action is usually applied with a small number of defendants, a single plaintiff, and a short time period between the tort and its discovery. The defendants’ joint plan is the basis of the cause of action, and most often the plaintiff is able to identify which defendant actually caused the injury. Abel v. Eli Lilly and Co., 418 Mich. 311, 338, cert. denied sub nom, E.R. Squibb & Sons, Inc. v. Abel, 469 U.S. 833 (1984).[15] The court stated that the identification did not preclude use of the theory. Id. According to the court, the only burden of plaintiffs to withstand a summary judgment motion, for failure to state a cause of action, was to “allege that the defendants were jointly engaged in tortious activity as a result of which the plaintiff was harmed.” Id. Inherent in this theory is the application of joint and several liability. As the Michigan court also stated, “[i]f plaintiffs can establish that all defendants acted tortiously pursuant to a common design, they will all be held liable for the entire result.” Id.*432 Even if we thought this theory appropriate in a Factor VIII case, again, we do not wish to burden defendants with joint and several liability. Therefore, we choose not to allow this theory to be applied to this case.

    C. Enterprise or Industry–Wide Liability

    The essence of the enterprise theory is that there is joint control of the risk throughout a particular industry. The theory originated in the blasting caps case, Hall v. E.I. DuPont de Nemours & Co., Inc., 345 F. Supp. 353 (E.D.N.Y.1972). The basis of the case was that there was an industry-wide standard concerning safety; the safety planning was delegated to a central group; and there was cooperation in the manufacture and design. Policy dictates that when all of those facts occur, the entire enterprise is liable. Therefore, the industry-wide standard became the cause of the plaintiff’s injury.

    The main premise against this theory is stated in one of the DES cases:

    The underlying rationale in all of the decisions rejecting enterprise liability is that the law of torts does not include a theory of liability which would allow an entire industry to be held strictly liable for an injury caused by a defective product. Enterprise liability as described in Hall is predicated upon industry-wide cooperation of a much greater degree than that alleged by the plaintiff.

    Martin v. Abbott Laboratories, 102 Wash.2d 581, 600 (1984). That premise is directly disputable by reading Hall, as the court states:

    There is thus no support for defendants’ argument that to establish joint control of risk, plaintiffs must demonstrate that the explosives industry was “rigidly *433 controlled” through the trade association with regard to blasting cap design, … and that the object of such control was some particularly reprehensible breach of duty. The variety of business and property relationships in which joint control of risk has been found demonstrates the flexibility of the doctrine. Liability is not limited to particular formal modes of cooperation, nor to illegal or grossly negligent activities.

    Hall v. E.I. DuPont de Nemours, 345 F. Supp. at 374.

    However, another court has aptly stated the plaintiff’s burden of proof with a showing:

    (1) that the product was manufactured by one of a small number of defendants in an industry; (2) the defendants had a joint capacity to reduce the risks of the product; and (3) each of them failed to take steps to reduce the risk at a substantially concurrent time by delegating their responsibility to an association.

    Conley v. Boyle Drug Co., 477 So.2d 600, 604 (Fla.App.1985), rev’d on other grounds, 570 So.2d 275 (Fla.1990) (specifically approving the analysis of the lower court as to alternative, concert of action, enterprise, and Sindell market share theories of liability).

    Based on the steps as set forth in Conley, the enterprise theory appears to be somewhat persuasive a method of approaching this case. We note that the pleadings do not raise the allegation that the defendants had the joint capacity to reduce the risk. Appellant does not even argue this theory in his opening brief; however, the facts alleged in the brief lend credibility to this type of argument. Were it not that we are again faced with the inherent application of joint liability, and the fact in addition, that we find one aspect of the Hall scenario convincingly distinguishable, we might endorse this theory in answer to the certified question.

    *434 First, we mention the distinguishable characteristic of Hall, which is convincingly pointed out to us by appellees and the court in Sindell v. Abbott Laboratories, 26 Cal.3d 588 (1980). The court there noted that “the drug industry is closely regulated by the Food and Drug Administration, … [t]o a considerable degree, therefore, the standards followed by drug manufacturers are suggested or compelled by the government.” Id., 163 Cal.Rptr. at 143. With the government in control of the parties’ actions, it is unfair to hold them liable for following the standards. Appellees’ arguments convince us that such reasoning is appropriate here, too, to eliminate this theory on these facts.

    We further digress to expound on our reluctance to adopt joint liability in the Factor VIII cases. First, as we are writing a new chapter in tort law in the State of Hawaii, we endeavor to set principles which we think would be adopted by our legislature. We note that by statute, joint and several liability in tort will be abolished to some extent as of October 1991. HRS § 663–10.9 (Supp.1990). As to what is still allowed, damages are still limited by the doctrine of modified comparative negligence. HRS § 663–31 (1985). Therefore, we believe the legislature has seen a need to balance the equities in this evolving field.

    In addition, as noted by many of the opinions in DES cases, there is an inherent unfairness in holding one or two parties responsible in full for the actions of tortfeasors who may escape liability for some reason. It seems at least a fair trade-off, where the plaintiff cannot identify which party actually caused his injuries, to at least allow the defendants to limit their share of liability to their relative proportion of the market. Therefore, we move on to discuss, and endorse, market share liability, with modifications.

    D. Market Share Liability & Its Progeny

    This theory has been most susceptible to variations and refinements, especially in DES litigation, but also in line with the *435 law of the state in which it has been applied. It was first defined in Sindell, 26 Cal.3d 588 (1980). The policies there stated included: 1. the reasoning of Summers v. Tice, 33 Cal.2d 80 (1948), that between innocent plaintiffs and negligent defendants, the negligent party should be held liable; 2. advances in science and the creation of fungible goods whose source cannot be traced; 3. the financial ability of defendants to bear the costs; and 4. the fact that manufacturers are in the better position to prevent defective products from reaching the consumer market. Sindell, 163 Cal.Rptr. at 144. We expand on those policies to acknowledge that defendants may bear the loss by passing that cost of doing business on to consumers. In addition, we feel that equity and fairness calls for using the market share approach. Another justification is that where many drugs can be lethal, and it is difficult for the consumer to identify the source of the product, the burden should shift. The concept itself meets the objectives of tort law, both by providing plaintiffs a remedy, but also by deterring defendants from negligent acts.

    After stating its policies, the Sindell court stated:

    [W]e hold it to be reasonable in the present context to measure the likelihood that any of the defendants supplied the product which allegedly injured plaintiff by the percentage which the DES sold by each of them for the purpose of preventing miscarriage bears to the entire production of the drug sold by all for that purpose.

    Id. at 145. Included in the definition was a requirement that a substantial percentage of the market must be joined as defendants, and that an exculpatory clause be included. Id. We feel that this basic theory, with modifications and distinctions to suit the policies of this state, discussed infra, provides an appropriate modem for appellant’s case. The relevant considerations *436 are: 1. defining the market, 2. identification and joint and several liability, and finally 3. exculpatory allowances.

    1. Defining the Market

    Criticisms of Sindell include the need for a definition of “substantial share” of the market, in order not to distort the share of liability. Martin v. Abbott Laboratories, 102 Wash.2d 581, 602 (1984). The Martin court adopted a narrow definition of the market, that being the plaintiff’s particular geographic market. Id. at 605. The justification is that the narrow market share purports to make a “particular defendant’s potential liability … proportional to the probability that it caused plaintiff’s injury.” Id. This policy was later reaffirmed by the same court, with acknowledgement that lacking evidence of the specific market, then “other figures, … such as within the county, state, or even in the country may in certain circumstances be introduced.” George v. Parke–Davis, 107 Wash.2d 584, 592 (1987). The Florida Supreme Court, in Conley v. Boyle Drug Co., 570 So.2d 275 (Fla.1990), agreed with the Washington court that the relevant market should be “as narrowly defined as the evidence in a given case allows.” Id. at 284. The court found this manner of definition to be consistent with the Martin theory of allowing a defendant to exculpate itself by showing no participation in that market. It does meet the goal of market-share liability to impose liability only on those companies who could have manufactured the injurious product.

    Another court has specifically adopted the national market as the best option. Hymowitz v. Eli Lilly and Co., 73 N.Y.2d 487, 511 (1989). Several premises supported this holding: 1. it was difficult to reliably determine any market smaller than the national one, 2. it avoided the need to establish separate *437 matrices as to market share, and 3. it avoided an unfair burden on litigants. Id. at 511. The national market was intended to “apportion liability so as to correspond to the over-all culpability of each defendant, measured by the amount of risk of injury each defendant created to the public-at-large.” Id. at 512. This provides equitable relief for plaintiffs, and a rational distribution of responsibility among defendants. It also avoids a windfall escape to the producer who happens to sell only to certain distributors. The culpability, therefore, is for marketing the product.

    As we are faced here with a minimal number of manufacturers of the product, we believe that culpability for marketing the product is a better policy. Should the issue arise under different circumstances at some point, we may find it appropriate to narrow the definition. For this case, however, we believe the national market is the more equitable consideration.

    2. Identification and Joint and Several Liability

    Courts differ on their requirements of an assertive effort on the part of plaintiffs to identify the actual manufacturer of the specific product which caused the harm. We take another approach to this concern. Whereas manufacturers here argue that appellant should have kept a log of which manufacturer’s product he was using, we fail to see how such failure affects the viability of appellant’s suit in view of our adoption of the theory of market share liability.

    Plaintiffs should use due diligence to join all manufacturers, but failure to do so is not a defense. Failure to do so may affect the percentage of recovery, discussed infra. However, manufacturers are permitted to implead other manufacturers. But, in this case, all manufacturers are joined, so the issue is not before us. However, we note in passing that the conditions of the Martin court, which would allow plaintiffs to initiate suit against only one defendant, *438 and of Sindell, which would require plaintiffs to join a “substantial” number of defendants, are immaterial as long as plaintiffs realize their recovery will depend on joining as many manufacturers as they can; plaintiffs will endeavor to join all manufacturers.

    We have already discussed our feeling that this action should not be subject to joint liability. We simply reiterate what other courts have said on this point, that “‘[t]he cornerstone of market share alternate liability is that if a defendant can establish its actual market share, it will not be liable under any circumstances for more than that percentage of the plaintiff’s total injuries.’ ” Conley, 570 So.2d at 285, quoting George v. Parke–Davis, 107 Wash.2d at 595. Therefore, we advocate several liability.

    We define the rules of distribution as to market share for this case as was done in Martin, that is:

    The defendants that are unable to exculpate themselves from potential liability are designated members of the plaintiffs’ … market[ ]…. These defendants are initially presumed to have equal shares of the market and are liable for only the percentage of plaintiff’s judgment that represents their presumptive share of the market. These defendants are entitled to rebut this presumption and thereby reduce their potential liability by establishing their respective market share of [Factor VIII] in the … market.

    Martin, 102 Wash.2d 581, 605 (1984). As to several liability, we adopt the theory that a particular defendant is only liable for its market share. Defendants failing to establish their proportionate share of the market will be liable for the difference in the judgment to 100 percent of the market. However, should plaintiff fail to name all members of the market, the plaintiff will not recover 100 percent of the judgment if the named defendants prove an aggregate share of less than 100 percent.

    3. Exculpatory Allowances

    As a result of our determination that a national market is appropriate, as long as defendant is actually one of the producers of Factor VIII, there is little to justify exculpation of defendant. However, the exception would occur where defendant could prove that it had no product on the market at the time of the injury. As far as the defendants in this suit are concerned, it appears that none of them would be able to escape liability on that basis.[16]

    In conclusion, we will recognize the basic market share theory of multi-tortfeasor liability, as defined herein. Acknowledging that this could open a Pandora’s box of questions, we believe that we have defined at least a starting point as to appropriately responding to the certified questions. However, as we are deciding issues in a virtual factual vacuum, we recognize that our opinion is limited to the facts presented to us, and we reserve the right to modify or amend our answers to these questions.

    MOON, Justice, concurring and dissenting.

    [***][T]he majority’s departure from well established tort law in Hawaii is based on a factual record that prevents plaintiff from establishing the existence of a legal duty and breach of *441 that duty, based on a provable standard of care, which is essential to the application of the market share theory of liability. [***]

    Initially, it is important to note that until today, negligence liability under Hawaii law required a plaintiff to prove by a preponderance of the evidence four essential elements: 1) the existence of a legal duty; 2) breach of that duty; 3) causation; and 4) injury. Knodle v. Waikiki Gateway Hotel, Inc., 69 Haw. 376 (1987). However, the market share liability theory imposes liability without requiring identification of the wrongdoers who caused plaintiff’s harm and shifts the burden to defendants to prove that they did not cause the plaintiff’s injury. Eliminating causation as an element of proof and shifting the burden to the defendant is [***] a radical departure from traditional negligence law. [***]

    In 1988, the American Medical Association reported that “in the pharmaceutical industry, meaningful product liability insurance has all but disappeared.” A.M.A., Report of the Board of Trustees on Impact of Product Liability on the Development of New Medical Technologies 2 (1988). This lack of insurance is largely due to the development of non-identification theories of liability.[17]

    *446 The application of the market share liability theory may result in liability being placed on defendants bearing no responsibility for the defective product and may create unpredictable costs to innocent parties [***] The primary authority cited by the majority in support of its position is the DES case of Sindell v. Abbott Laboratories, 26 Cal.3d 588, cert. denied, 449 U.S. 912 (1980), which was the first to judicially promulgate the market share liability theory. In Sindell, the “DES daughter” plaintiff sought to recover damages for injuries resulting from cancer caused by DES, a miscarriage preventative. The mother ingested the drug over twenty years prior to the cause of action being filed. The trial court dismissed the action on the ground that plaintiff had conceded that the specific manufacturers of the drug could not be identified.

    On appeal, the Supreme Court of California adopted the market share liability theory, which relieved plaintiff of the burden of identifying which of over 200 companies manufactured the DES drug ingested by her mother. The court, in reaching this *447 conclusion, reasoned: “In our contemporary complex industrialized society, advances in science and technology create fungible goods which may harm consumers and which cannot be traced to any specific producer.” Sindell, 26 Cal.3d at 610. The court determined that two essential factual elements, fungibility and the inability to identify specific producers, must be present in order for the market share liability theory to be appropriate. Both elements are glaringly absent in the Factor VIII case before us. [***]

    The primary authority cited by the majority in support of its position is the DES case of Sindell v. Abbott Laboratories, 26 Cal.3d 588, cert. denied, 449 U.S. 912 (1980), which was the first to judicially promulgate the market share liability theory. In Sindell, the “DES daughter” plaintiff sought to recover damages for injuries resulting from cancer caused by DES, a miscarriage preventative. The mother ingested the drug over twenty years prior to the cause of action being filed. The trial court dismissed the action on the ground that plaintiff had conceded that the specific manufacturers of the drug could not be identified.

    On appeal, the Supreme Court of California adopted the market share liability theory, which relieved plaintiff of the burden of identifying which of over 200 companies manufactured the DES drug ingested by her mother. The court, in reaching this *447 conclusion, reasoned: “In our contemporary complex industrialized society, advances in science and technology create fungible goods which may harm consumers and which cannot be traced to any specific producer.” Sindell, 26 Cal.3d at 610. The court determined that two essential factual elements, fungibility and the inability to identify specific producers, must be present in order for the market share liability theory to be appropriate. Both elements are glaringly absent in the Factor VIII case before us. [***]

    IV. Judicial Restraint

    The majority’s primary reason for adopting the market share liability theory, in a form that is even more expansive than in Sindell, is that “the harshness of the result, that is, burdening the innocent plaintiff without a remedy, to us seems totally unfair and out of step with current efforts to allow recovery when the proper case is brought.”

    I, too, sympathize with Smith’s tragic situation. However, this court has been faced with similar situations and has applied judicial restraint by declining to expand established principles of the common law merely to provide a remedial measure. [***]

    I submit that this court is again confronted with an issue which it is ill-equipped to rule upon. There are too many unanswered questions of social, economic, and legal import, which only the legislature, with its investigative powers and procedures, can determine. Deference to the legislature is especially appropriate due to the legislature’s enactment of the blood shield statute and the impact that any non-identification theory such as market share may have on the blood products industry.

    Furthermore, I disagree with the majority’s statement that Hawaii would be “out of step with current efforts to allow recovery when the proper case is brought.” As defendant Cutter Biological notes in its answering brief, since the initial adoption of market share liability in Sindell, the highest courts of only four other states have adopted that theory. Conley v. Boyle Drug Co., 570 So.2d 275 (Fla.1990) (DES case); Hymowitz v. Eli Lilly & Co., 73 N.Y.2d 487, cert. denied, 493 U.S. 944, (1989) (DES case); Collins v. Eli Lilly & Co., 116 Wis.2d 166, cert. denied, 469 U.S. 826 (1984) (DES case); Martin v. Abbott Laboratories, 102 Wash.2d 581 (1984) (DES case).

    Four state supreme courts have rejected the market share theory of liability doctrine: Smith v. Eli Lilly & Co., 137 Ill.2d 222 (1990) (DES case); Shackil v. Lederle Laboratories, 116 N.J. 155 (1989) (DPT vaccine case); Mulcahy v. Eli Lilly & Co., 386 N.W.2d 67 (Iowa 1986) (DES case); and Zafft v. Eli Lilly & Co., 676 S.W.2d 241 (Mo.1984) (DES case).

    *456 A number of federal courts have also rejected the doctrine: Tidler v. Eli Lilly & Co., 851 F.2d 418 (D.C.Cir.1988) (DES case); Morton v. Abbott Laboratories, 538 F.Supp. 593 (M.D.Fla.1982) (DES case); Mizell v. Eli Lilly & Co., 526 F.Supp. 589 (D.S.C.1981) (DES case); Ryan v. Eli Lilly Co., 514 F.Supp. 1004 (D.S.C.1981) (DES case). An empirical study of this issue concluded that “[i]n the last several years decisions in a number of jurisdictions clearly indicate that courts are in no mood to extend that expansionary doctrine [market share liability] any further.” Henderson & Eisenberg, The Quiet Revolution in Products Liability: An Empirical Study of Legal Change, 37 U.C.L.A. L. Rev. 479, 492 (1990) (emphasis added).

    The Iowa Supreme Court in Mulcahy v. Eli Lilly & Co., 386 N.W.2d 67 (Iowa 1986), aptly states some of the basic reasons why non-identification theories, which eliminate causation as an element of plaintiff’s proof, should not be adopted by the courts:

    We acknowledge that plaintiff in a DES case with an unidentified product manufacturer presents an appealing claim for relief. Endeavoring to provide relief, courts have developed theories which in one way or another provided plaintiffs recovery of loss by a kind of court-constructed insurance plan. The result is that manufacturers are required to pay or contribute to payment for injuries which their product may not have caused.

    This may or may not be a desirable result. We believe, however, that awarding damages to an admitted innocent party by means of a court-constructed device that places liability on manufacturers who were not proved to have caused the injury involves social engineering more appropriately within the legislative domain. In order to reach such a determination, three broad policy questions must be answered. One is whether the burden *457 of damages for these injuries should be transferred in a constitutional manner to the industry irrespective of an individual manufacturer’s connection with the particular injury. If so, the second question relates to the principles and procedures by which the burden would be transferred. Finally, how do we ascertain the extent of damages to be assessed against each manufacturer? … Plaintiffs request that we make a substantial departure from our fundamental negligence requirement of proving causation, without previous warning or guidelines. The imposition of liability upon a manufacturer for harm that it may not have caused is the very legal legerdemain, at least by our long held traditional standards, that we believe the courts should avoid unless prior warnings remain unheeded. It is an act more closely identified as a function assigned to the legislature under its power to enact laws.

    Mulcahy v. Eli Lilly Co., 386 N.W.2d 67, 75–77 (Iowa 1986).

    Leaving plaintiff without a remedy is a harsh result, however, this is not the proper case upon which this court should innovate and radically change the existing law. The application of market share liability in the context of this case would essentially make each defendant manufacturer an insurer of any infected individual who “might” or “could” have used its Factor VIII concentrate. [***] [S]uch a broad imposition of liability is wholly unjustified, unfair, and likely to discourage the future development and sale of blood therapies. The decision of whether such an expansive theory *458 of liability should apply as against manufacturers of blood products is best left to the legislature, which is equipped to address the “Pandora’s box” of questions that the majority acknowledges results by today’s decision.

    I submit that the majority is mistaken if its characterization of the record as a “virtual factual vacuum” means that the facts are insufficient, and thus a trial is necessary to develop additional facts in this case. Additional facts will not change the inevitable—that is, Smith’s inability to establish when and how he was infected by the HIV virus, and the fact that information regarding AIDS and the techniques to detect the HIV virus were just being developed during the pertinent period, make it impossible for Smith to prove a standard of care. The majority’s decision now allows all of the parties to proceed to trial, which undoubtedly will result in substantial costs and attorneys’ fees being incurred. However, the expenditure of time and money will be for naught.

    Note 1. What is the significance of the court’s declining to adopt alternate liability, enterprise or industry-wide liability and joint and several liability but allowing market share liability? What is the likely effect of that scope? How does the court delimit the scope of market share liability further?

    Note 2. The majority opines that “tort law is a continually expanding field.” Yet in judicial opinions declining to expand the scope of tort law, you have likely seen statements to the contrary, or arguments against tort law’s expansion. What justification does the court offer here for the need for such expansion in the case at bar?

    Note 3. What are the dissent’s arguments against the application of market share liability? Which opinion is more persuasive to you and why?

    Note 4. In a footnote, the majority opinion distinguishes prior case law that found it was a breach of duty that defendant had not “use[d] “’high risk’ questioning as to the specifics of whether the donor was a homosexual [c]. …the donor, who was clearly identified, would not and did not admit that he was a member of one of the ‘high risk’ groups for AIDS.” At the height of the AIDS epidemic, fears of contagion and misunderstanding about the disease were rampant.

    As the COVID-19 pandemic gripped the world in 2020 and 2021, many of the same fears and controversies about infectiousness and contagion vectors arose. A recent essay shared the perspective of one man who drew parallels between the two eras: “From the number of complaints I’m hearing of pandemic fatigue and the widespread resistance to simple precautionary measures such as wearing a mask at the grocery store, it’s clear to me that many people don’t fully appreciate what the gay community has been dealing with for the past 40 years and don’t understand how we survived the AIDS epidemic.” (September 25, 2020)

    It was almost certainly more difficult socially to come out as bisexual, gay or transgender in the 1980s and AIDS ramped up the challenges by layering on irrational fears of contagion. What do you think of tort cases considering whether a party breached its duty in some way by not asking about a plaintiff’s sexual orientation? Was it understandable—as a public health matter—to hold a party liable for not inquiring if evidence proved that sexual orientation was correlated with higher risk of AIDS? Or should a sense of privacy, propriety, dignity, or some combination of those have been permitted to shield providers and patients from a legal obligation to ask?

    Would your answer change if it turned out that the reason for providers not wanting to broach the topic with patients carried legal consequences for patients, such as loss of a job or cancellation of medical insurance, that providers wished to avoid? How about if providers simply wished to avoid asking because they wanted to provide safe (and often free) medical care in the community without patients’ fearing that their sexual orientation would be outed? What if evidence suggested that patients wouldn’t seek testing if they knew they had to reveal their sexual orientation? What is tort law’s responsibility, if any, to take such factors into account when considering what is reasonable under the circumstances?

    Expand On Your Understanding – Causation Hypotheticals

    Review the following hypotheticals. Turn each card to reveal the answer.

    The original version of this chapter contained H5P content. You may want to remove or replace this element.

    1. As noted, plaintiffs’ first specification does not allege negligence in the design of the refuse transfer station. Instead, the specification charges negligence in “failing to maintain” a facility with barriers to protect patrons from falling over the edge of the platform. We agree with the county, however, that the gravamen of that allegation is that the county’s alleged failure to design the platform in a way that included protective barriers (other than the railroad tie that prevented vehicles form backing up too far) made the platform unreasonably dangerous.
    2. In England the requirement of fault in cases of direct injury to plaintiffs by defendants is generally dated to Baron Bramwell’s opinion in Holmes v. Mather, 10 Exch. 261 (1875) [c]. In many of the states of the United States the requirement was imposed earlier. The opinion most frequently cited is that of Chief Justice Lemuel Shaw in Brown v. Kendall, 60 Mass. (6 Cush.) 292 (1850) [c].
    3. The requirement of causation was a well-recognized and essential element of the plaintiff's case in chief in 17th century trespass actions such as Weaver v. Ward, Hobart 134, 80 Eng. Rep. 28 (K.B.1617) [c] and Gibbons v. Pepper, 1 Ray. 38, 91 Eng. Rep. 922 (K.B.1695) [c]. The action in trespass, and especially trespass vi et armis (along with the later action of trespass on the case), is generally regarded as the ancestor of the modern personal injury suit.
    4. See Michie v. Great Lakes Steel Div., 495 F.2d 213 (6th Cir.1974).
    5. In Daubert, the Supreme Court rejected the traditional Frye rule (which had required that a scientific theory be generally accepted by the scientific community to be admissible, see Frye v. United States, 293 F. 1013, 1014 (D.C.Cir.1923)), concluding that adherence to Frye’s “rigid ‘general acceptance’ requirement would be at odds with the ‘liberal thrust’ of the Federal Rules [of Evidence].” Daubert, 509 U.S. at 588 (citations omitted).
    6. In non-negligence cases, the same requirement applies as to those non-faulty acts or activities (e.g., product defects, extra-hazardous behavior) on whose existence the potential liability is grounded. In the last fifty years the strictness of the requirement that the plaintiff show that without defendant’s act or omission the accident would not have occurred has been mitigated in several types of cases. For instance, where two defendants are both clearly at fault, where the plaintiff has little or no information as to which one's negligence was responsible for the injury, and especially where the defendants may have better access to such information, the modern trend is to place the burden on the defendants to disprove causation. See, e.g., Summers v. Tice, 33 Cal.2d 80 (1948); see also, Modave v. Long Island Jewish Med. Ctr., 501 F.2d 1065 (2d Cir. 1974) (Friendly, J.) (suggesting that, under New York law, a plaintiff may not need to prove which of two culpable defendants actually caused the plaintiff’s injury even when the defendants were probably no more able to show what happened than was the plaintiff). Another important example of this easing trend has been the acceptance of statistical or market share evidence as a means of assigning at least part of a loss to various defendants whose conduct justified liability but who could not be identified, more probably than not, as having been but for causes of it. See, e.g., Sindell v. Abbott Labs., 26 Cal.3d 588 (1980); Hymowitz v. Eli Lilly & Co., 73 N.Y.2d 487 (1989). Many courts long ago abandoned the requirement of but for cause in situations where, since the negligence of any one of several defendants was sufficient to cause the harm, the negligence of none was its necessary cause. See, e.g., Corey v. Havener, 182 Mass. 250 (1902). Indeed, some commentators attribute the acceptance of the “substantial factor” terminology, such as that used in Connecticut, to the problems a strict but for test would cause in this latter type of case. See, e.g., W. Page Keeton et al., Prosser and Keeton on the Law of Torts § 41, at 267–68 (5th ed.1984) [hereinafter Prosser]. While none of these easings in the requirement of proof of but for cause applies directly to the case before us, it is not unlikely that developments that are relevant to the instant case, see infra section II(B)(4), derived from a desire to achieve analogous goals through tort law. See generally Guido Calabresi, Concerning Cause and the Law of Torts: An Essay for Harry Kalven, Jr., 43 U. Chi. L. Rev. 69 (1975).
    7. Although Ray is listed as an Appellant in the Opening Brief, it appears that she is involved in this case only to the extent that D.M.’s claims are brought by and through Ray. We will therefore refer to the appealing party in the singular.
    8. Under the Section 8 Program, tenants pay rent “based on their income and ability to pay. The PHA then makes ‘housing assistance payments’ to private landlords” that equals “the difference between the [tenant’s] contribution and a ‘contract rent’ agreed upon by the landlord and the PHA.” Truesdell v. Phila. Hous. Auth., 290 F.3d 159, 161 (3d Cir. 2002).
    9. Plaintiff concedes that the lead paint was present when Ray and D.M. moved into the Property.
    10. Plaintiff’s attempts to distinguish Henry are unpersuasive. In Henry, the plaintiffs alleged that Erie, Pennsylvania’s housing authority caused their injury by allowing them to reside in a location without smoke detectors or fire alarms. 728 F.3d at 285. In this case, Plaintiff alleges that the PHA wrongly permitted Ray and D.M. to reside in a location in which lead paint was present. Henry rejected this as a basis for liability because the Erie housing authority's actions were not the fairly direct cause of the injury. The cause of the Henry injury was the fire and the alleged cause of D.M.'s injury was the lead paint placed there by the landlord. Thus, Henry is indistinguishable.
    11. The first distinction is that jurisdictionally, those courts’ decisions are not controlling here. Second, in Jones, the negligence was based on the failure of the defendant to use “high risk” questioning as to the specifics of whether the donor was a homosexual. Jones, 887 F.2d at 1580. The decision was based solely on the fact that the donor, who was clearly identified, would not and did not admit that he was a member of one of the “high risk” groups for AIDS. Id. at 1581. In McKee, the finding of no negligence was based on the fact that at the time of the decedent’s being diagnosed with AIDS, in October 1983, industry custom did not require the processes developed later to inactivate the AIDS virus. McKee, 866 F.2d at 224. A final distinction is that in both cases, the specific manufacturer was named. On the other hand, at least one court has approved application of the market share theory of liability on facts similar to those herein. Ray v. Cutter Laboratories, 754 F.Supp. 193 (M.D. Fla. 1991). Ray was also considered at the summary judgment stage, but the federal court adopted the market share theory as that was the only multi-tortfeasor theory of liability then approved by the state supreme court. Id. at 195.
    12. Defendants include not only the manufacturers—Armour Pharmaceutical Corporation, Cutter Biological, Inc., Alpha Therapeutics Corporation, and Travenol Laboratories, Inc. (now Baxter Laboratories)—but also the United States of America (U.S.). The allegations against the U.S. are based on negligence and failure to warn. Although designated as an appellee, the U.S. has not filed an answering brief. We note that the claims against the U.S. are not directly pertinent to the certified questions before this court.
    13. AIDS is an infectious disease caused by a virus, as are herpes, smallpox, yellow fever, and hepatitis. R. Jarvis, M. Closen, D. Hermann, A. Leonard, AIDS LAW in a Nutshell 1 (West Publishing 1990) (hereinafter AIDS Nutshell). The disease was uniquely recognized in June and July, 1981. Id. at 5. There are several modes of infection: 1. sexual intercourse, 2. sharing infected syringes, 3. receipt of human tissue, blood, etc., and 4. child birth or breast feeding. Id. at 7. Once infected, a victim will not test positive for HIV during a “window” period, which lasts between six weeks and six months—although some researchers say the window period may be several years. Id. at 14. Although testing positive, a person may continue to be asymptomatic for seven to ten years. Id.
    14. Appellant, at one point, attempted to convert this suit to a class action, but failed to follow through on the opportunity. Our analysis of the theories of liability might differ, were this a class action.
    15. The Michigan court allowed this theory to be applied in a DES case, which had reached the court on summary judgment, where it appeared the plaintiff could identify the tortfeasor. Abel v. Eli Lilly & Co., 418 Mich. 311, 343 N.W.2d 164, cert denied, 469 U.S. 833, 105 S. Ct. 123, 83 L. Ed. 2d 65 (1984).
    16. The precursor of the DES cases is Sindell v. Abbott Laboratories, 26 Cal.3d 588 cert. denied, 449 U.S. 912 (1980). Sindell arose when demurrers were sustained as to several manufacturers of DES, on the basis that plaintiff could not identify whose product caused the injury. Id., 163 Cal.Rptr. at 134, n. 3. The Sindell court considered the four main theories. Michigan approved both the concert of action and alternate liability theories in a DES case up on summary judgment. Abel v. Eli Lilly and Co., 418 Mich. 311 (1984). In the same year, the Washington Supreme Court addressed the issue on appeal from summary judgment, in Martin v. Abbott Laboratories, 102 Wash.2d 581 (1984). The Martin court reanalyzed the theories enumerated in Sindell, and then created the market-share alternate liability. A federal court in Illinois tentatively allowed the alternate liability theory in a DES case, acknowledging that the Illinois Supreme Court had not yet addressed the issue. Poole v. Alpha Therapeutic Corp., 696 F.Supp. 351 (N.D.Ill.1988). Later, the Illinois Supreme Court did address a DES case, but only as to the market share theory of liability—which it refused to adopt. Smith v. Eli Lilly & Co., 137 Ill.2d 222 (1990). In New York, as in Florida, state courts adopted market share theories as viable in DES cases. Hymowitz v. Eli Lilly and Co., 73 N.Y.2d 487 (1989) (on certified questions, and adopting the national market as the base market); Conley v. Boyle Drug Co., 570 So.2d 275 (Fla.1990) (adopting Washington's version of market share liability, and summarily disposing of the other theories).
    17. See United States Department of Justice, Report of the Tort Policy Working Group on the Causes, Extent and Policy Implication of the Current Crisis in Insurance Availability and Affordability 33–35 (Washington, D.C. Government Printing Office, Feb. 1986).

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