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7.6: End-of-Chapter Material

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    The bedrock principle of the criminal justice system is the presumption of innocence. All defendants, no matter how strong the evidence may appear, begin a trial with a clean slate. All are presumed innocent of the crime charged. For this reason, a defendant can simply rely on the government to fail to prove the defendant’s guilt beyond a reasonable doubt. Such a defense is referred to as a failure of proof defense. Most defenses found within criminal law are statutory. A perfect defense results in the defendant being acquitted of the crime charged. An imperfect defense results in the defendant being convicted of a less serious, but related crime. A criminal defense requires the government to disprove its existence beyond a reasonable doubt, similar to a failure of proof defense. An affirmative defense raises an issue separate from the elements of the offense where the defendant has the burden of persuasion by a preponderance of the evidence. A factual defense is grounded in the facts of the case, while a legal defense depends on a statute or common-law principle. An example of a factual defense is an alibi defense, which asserts that the defendant could not have committed the crime because he was not present at the time the crime occurred. An example of a legal defense is the expiration of the statute of limitations, which means it is too late to prosecute the defendant for the offense.

    Defenses are also categorized as either a justification or an excuse. A justification defense focuses on the offense and deems the conduct worthy of protection from criminal responsibility. An excuse defense focuses on the defendant and excuses his or her conduct under the circumstances.

    Self-defense justifies the defendant’s conduct in using physical force to protect oneself. The government is required to disprove self-defense beyond a reasonable doubt and it is a perfect defense. Self-defense is based on two basic elements – necessity and proportionality. Self-defense is only available if the defendant faces an unprovoked, imminent attack and the degree of force used in response is necessary to avoid the attack and was objectively reasonable under the circumstances. Fear of likely, future harm is insufficient to satisfy the imminency requirement of self-defense. Deadly force is any force that can kill under the circumstances. Deadly force can be used in self-defense only if the defendant is faced with imminent death, serious bodily injury, or the commission of a serious felony. A defendant need not retreat before resorting to deadly force, provided that the defendant is in a place he is legally entitled to be – trespassers must retreat before using deadly force.

    A person may defend another to the same extent as the person may defend themselves under the law of self-defense. If a defendant honestly, but reasonably mistakes the need to defend another, the defendant may still claim the defense of others. A defendant may use nondeadly force to prevent the imminent threat of damage, loss, or theft of property. Real property is land and anything permanently attached to it, while personal property is any movable object. A trespasser may be ejected from real property using nondeadly force.

    A person may use deadly force to prevent arson or burglary of an occupied dwelling. This expanded use of force is referred to as the castle doctrine. A person may not use deadly force to prevent arson or burglary of an unoccupied building. The defense of habitation focuses on the protection of life within the building, and not on the property itself.

    Law enforcement has the right to use force in circumstances beyond that of an ordinary citizen. A law enforcement officer may use reasonable nondeadly force, and threaten the use of deadly force, when arresting a criminal suspect, making a lawful investigatory stop, and when recapturing an escapee. A police officer may use deadly force when the officer reasonably believes deadly force is necessary to arrest a person committing a violent felony, escape from prison while armed, or if the person is engaging in highly dangerous behavior likely to result in death or serious injury. The level and degree of force are considered seizures under the Fourth Amendment and are analyzed under an objectively reasonable standard.

    The defense of necessity permits the defendant to commit a crime if the harm caused is less severe than the harm that will occur if the crime is not committed. Necessity is sometimes referred to as the choice of evils defense. Duress, a closely related defense, can justify criminal behavior if the defendant is imminently threatened with serious bodily injury or death.

    Consent may also be a defense to criminal liability, but is normally analyzed under a failure of proof defense. The victim may consent to the defendant’s conduct provided that the consent was given knowingly and voluntarily. Consent is normally a defense to sex offenses, or conduct occurring during a sporting event, and the conduct does not involve serious bodily injury or death.

    Key Takeaways

    • A failure of proof defense focuses on the elements of the crime and prevents the prosecution from meeting its burden of proof. An affirmative defense is a defense that raises an issue separate from the elements of the crime. Affirmative defenses require the defendant to prove the defense by a preponderance of the evidence.
    • An imperfect defense reduces the severity of the offense; a perfect defense results in an acquittal.
    • A justification defense asserts that the defendant’s criminal conduct was justified under the circumstances. An excuse defense asserts the defendant should be excused for their conduct.
    • If the basis for a defense is an issue of fact, it is called a factual defense. If the basis for a defense is an issue of law, it is called a legal defense.
    • Self-defense is a defense based on the justification that allows a defendant to use physical force to protect herself from harm
    • Deadly force is any force that can produce death or serious injury. An individual does not have to die for the force to be deemed deadly.
    • Self-defense is built upon the assumption that the force used was necessary and proportional to the harm faced. A person may only use self-defense when faced with an imminent threat of harm. Likely, future harm is insufficient to justify self-defense. A defendant may only use an objectively reasonable degree of force in response to an objectively reasonable fear of harm.
    • Deadly force is appropriate in self-defense when the attacker threatens death, serious bodily injury, or specific serious felonies.
    • The duty to retreat doctrine is a common-law rule requiring a defendant to retreat if it is safe to do so, instead of using deadly force in self-defense. The stand-your-ground doctrine is a rule allowing the defendant to use deadly force if appropriate in self-defense, rather than retreating.
    • Defense of others has the same elements as self-defense: the individual defended must be facing an unprovoked, imminent attack, and the defendant must use a reasonable degree of force with a reasonable belief that force is necessary to repel the attack.
    • The defendant can use nondeadly force to defend real or personal property if the defendant has an objectively reasonable belief that an imminent threat of damage, destruction, or theft will occur.
    • Property owners can use reasonable nondeadly force to eject a trespasser.
    • Only nondeadly force may be used to defend property; deadly force may be used to defend against an arson or burglary of an occupied building.
    • Use of force by law enforcement is considered a seizure under the Fourth Amendment, so law enforcement cannot use deadly force to apprehend or arrest a criminal suspect unless there is probable cause to believe the suspect will inflict serious physical injury or death upon the officer or others.
    • Three elements are required for the defense of necessity: the criminal act must be done to prevent a significant evil, there was no adequate alternative, and the harm caused must not have been disproportionate to the harm avoided.
    • Choice of evils is often based on nature or an act of God; duress is generally brought on by another individual.
    • Two elements are required for the consent defense: the defendant must consent knowingly (cannot be too young, mentally incompetent, or intoxicated) and voluntarily (cannot be forced, threatened, or tricked).
    • Three situations where consent can operate as a defense are sexual offenses, situations that do not result in serious bodily injury or death, and sporting events.

    Answers to Exercises

    From Other Us-of-Force Defenses

    1. Melanie cannot use the defense of others as a defense to murder. Melanie can defend Colleen only to the same extent she could defend herself. Nothing in the fact pattern indicates that Colleen could defend herself using deadly force. Thus, Melanie could be successfully prosecuted for criminal homicide in this situation.

    Answer to Is Cannibalism a Crime?

    In Regina v. Dudley & Stephens, 14 Q.B.D. 273 (1884) an English court found the shipwreck survivors guilty of murder and sentenced them to death (later commuted to six months in jail). While the men sought to justify their actions based on necessity, the court rejected the defense. Human life, according to the court, is paramount. Human life should be protected if at all possible. Neither probable nor likely death justifies cold-blooded murder. Killing another human being is only allowed when life itself is physically threatened. Otherwise, the law would be required to determine whose life was paramount. The circumstances that led to the killing of Richards (the teenage boy) was murder, especially when Richards was given no choice in the matter.

    Joseph Simeone’s essay, “Survivors” of the Eternal Sea: A Short True Story, 45 St. Louis U. L.J. 1123 (2001) provides a much more thorough and complete description of the events. Simeone’s essay is available through the Consortium Library at the University of Alaska Anchorage using your student credentials.

    Answers to You Be the Judge…

    Answer to You Be the Judge … (7.1)

    • Jennifer likely has a valid defense of necessity for her initial decision to drive away from her boyfriend. Physical harm is a significant evil; Jennifer has the right to avoid injury. Fleeing instead of waiting for police to arrive is an appropriate alternative. Finally, driving intoxicated to prevent immediate physical harm is not disproportionate to the harm caused by driving. However, the necessity likely ended when Jennifer drove past a police station, a shopping mall, and open businesses. To claim necessity, Jennifer must stop violating the law as soon as its danger is averted. Compare Reeves v. State, 764 P.2d 324 (Alaska App. 1988) and Greenwood v. State, 237 P.3d 1018 (Alaska 2008). Both Reeves and Greenwood involved substantially similar fact patterns – a victim of domestic violence driving intoxicated to avoid being assaulted. In Reeves, the court found the victim did not have a necessity defense because she did not stop at the police station, but instead drove past a family member’s home. Conversely, in Greenwood, the court found the victim did have a valid necessity defense in part because she fled the house to a well-lit parking lot and flagged down the oncoming police officer.

    Answer to You Be the Judge (7.2)

    • Juan has demonstrated all of the elements of duress: immediacy, a well-grounded fear, and inescapability. Juan reasonably believed his family would be immediately killed if he did not comply and his alternative was either go to the police or flee, forcing him to leave his family in peril. The law only requires a defendant to act reasonably. Here, Juan presented a triable claim of duress. See U.S. v. Contento-Pachon, 723 F.691, 693-94 (9th Cir. 1984).

    This page titled 7.6: End-of-Chapter Material is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Rob Henderson via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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