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2: The Fourth Amendment

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    • 2.1: Chapter 2 - What Is a Search? The Basics
      This page explores the Fourth Amendment's protection against unreasonable searches, emphasizing personal privacy, as illustrated by key cases like Katz v. United States and United States v. Jones. Katz established that privacy extends beyond physical spaces, while Jones highlighted the implications of GPS tracking on privacy expectations.
    • 2.2: Chapter 3 - What Is a Search? Some Specifics
      This page explores the application of the Fourth Amendment regarding privacy in searches, focusing on cases involving garbage searches, thermal imaging, and tracking technologies. The Supreme Court's rulings often find no reasonable expectation of privacy in public trash or in data shared with companies, invoking dissent on privacy intrusions. Discussions on technological advancements highlight concerns over surveillance and personal privacy rights.
    • 2.3: Chapter 4 - What Is a Search?- More Specifics
      This page discusses the Fourth Amendment's protection against unreasonable searches, particularly concerning open fields where warrantless searches are permitted. Key cases, like Ray Oliver v. United States and United States v. Dunn, reaffirm this "open fields" doctrine, distinguishing curtilage from open fields. Dissenting opinions challenge these views, arguing for privacy rights, especially regarding aerial surveillance.
    • 2.4: Chapter 5 - What Is a Search?- Wrapping Up
      This page examines the evolving legal landscape regarding privacy rights and the Fourth Amendment in the context of digital data collection and law enforcement practices. It discusses a significant court ruling on historical cell phone location data, prompting concerns over privacy expectations and implications for police investigations.
    • 2.5: Chapter 6 - Probable Cause and Reasonable Suspicion
      This page explores various legal cases related to the Fourth Amendment, emphasizing the concept of "probable cause" in searches and arrests. It critiques the rigid interpretation of informants' tips, advocating for a totality-of-the-circumstances approach. The text reflects on the Supreme Court's rulings, like Illinois v. Gates and Whren v. United States, which reinforce that probable cause is the primary criterion for legality despite officers' intentions.
    • 2.6: Chapter 7 - Warrants
      This page discusses the legal requirements for search warrants under the Fourth Amendment, highlighting the necessity of probable cause, specificity, and a neutral magistrate's issuance. It explores various court cases, illustrating differing opinions on warrant validity and the implications of no-knock warrants, emphasizing the balance between law enforcement needs and civil liberties. The principle of "knock and announce" is examined, along with exceptions to it.
    • 2.7: Chapter 8 - Execution of Warrants
      This page summarizes legal considerations surrounding the execution of search warrants and the detention of individuals. The Supreme Court upheld the reasonable use of handcuffs during a search for safety, while also critiquing excessive force and questioning durations. It clarifies that police can detain individuals on-site but not those who leave beforehand. Various cases highlight the importance of probable cause, warrant specificity, and the balance between safety and Fourth Amendment rights.
    • 2.8: Chapter 9 - Warrant Exceptions
      This page examines exceptions to the Fourth Amendment warrant requirement, focusing on the "plain view" and "automobile" exceptions through key legal cases. The summary highlights the significance of judicial oversight in searches, the balance between privacy rights and police powers, and the evolving interpretations of probable cause regarding warrantless searches of vehicles and their containers.
    • 2.9: Chapter 10 - The Warrant Requirement- Exceptions (Part 2)
      This page examines the legal standards for searches incident to lawful arrest (SILA) under the Fourth Amendment, highlighting significant Supreme Court cases like Chimel v. California, Arizona v. Gant, and Riley v. California. It discusses limits on warrantless searches, particularly concerning vehicles and digital data on cell phones, underscoring the necessity for probable cause and the protection of privacy rights.
    • 2.10: Chapter 11 - The Warrant Requirement- Exceptions (Part 3)
      This page discusses the legal nuances of consent searches in the context of the Fourth and Fourteenth Amendments. The Supreme Court clarified that awareness of the right to refuse consent is not essential for valid consent, emphasizing the totality of circumstances to gauge voluntariness. Dissenting justices warn that this undermines constitutional protections when individuals lack awareness of their rights.
    • 2.11: Chapter 12 - The Warrant Requirement- Exceptions (Part 4)
      This page examines the concept of "exigent circumstances" that permits warrantless searches by law enforcement under specific threats to public safety, urgency, or evidence preservation. Key Supreme Court cases, including Warden v. Hayden, Payton v. New York, Brigham City v. Stuart, and Kentucky v. Hollis Deshaun King, highlight the tensions between individual privacy rights under the Fourth Amendment and the need for swift police action.
    • 2.12: Chapter 13 - The Warrant Requirement- Exceptions (Part 5)
      This page discusses various Supreme Court cases related to warrantless blood and breath tests in drunk-driving cases, emphasizing the need for case-by-case assessments of exigent circumstances. The Court ruled that the natural metabolism of alcohol does not automatically justify warrantless blood tests, and warrants should be obtained when feasible to protect individual privacy rights.
    • 2.13: Chapter 14 - The Warrant Requirement- Exceptions (Part 6)
      This page explores the legal framework governing searches, seizures, and stops at U.S. borders under the Fourth Amendment. It highlights various Supreme Court cases justifying extensive authority for border searches and vehicle stops at checkpoints without warrants or individualized suspicion, citing national security and immigration control. Dissenting opinions express concerns about erosion of civil liberties and potential discrimination.
    • 2.14: Chapter 15 - The Warrant Requirement- Exceptions (Part 7)
      This page examines the legality and effectiveness of warrantless searches and police checkpoints, focusing on sobriety and narcotics checkpoints. It highlights the Supreme Court's rulings, such as in Michigan State Police v. Rick Sitz and Illinois v. Lidster, balancing state interests against individual privacy. The dissenting opinions raise concerns over privacy rights and the requirement for probable cause.
    • 2.15: Chapter 16 - The Warrant Requirement- Exceptions (Part 8)
      This page analyzes the legality of searches by school officials and public employers under the Fourth Amendment, focusing on landmark cases like New Jersey v. T.L.O. and Safford Unified School District v. Redding. It discusses the balance between individual privacy rights and institutional safety, arguing that while school searches must be reasonable, they also require justification to avoid violating student rights. Additionally, it covers City of Ontario v.
    • 2.16: Chapter 17 The Warrant Requirement - Exceptions
      This page examines the legality of drug testing in public schools and among employees, focusing on Supreme Court rulings regarding the balance between safety interests and Fourth Amendment rights. Key cases include *Vernonia* and *Earls*, which uphold drug testing for student athletes and extracurricular participants, citing safety concerns. However, dissenting opinions stress the importance of privacy rights and the potential for governmental overreach.
    • 2.17: Chapter 18 The Warrant Requirement - Exceptions
      This page examines various legal precedents regarding searches under the Fourth Amendment, particularly focusing on strip searches in jails, police automobile searches, warrantless inspections, and DNA collection from arrestees. The Supreme Court generally upholds expansive search practices for safety and identification purposes, emphasizing government interests while acknowledging dissenting opinions against invasive searches without reasonable suspicion.
    • 2.18: Chapter 19 - Seizures and Arrests
      This page discusses multiple Supreme Court rulings on the Fourth Amendment, emphasizing the complexities of "seizure" and consent during police encounters. In Mendenhall, the court found no constitutional violation regarding the DEA's questioning approach. Hodari D. established that pursuit alone does not equate to seizure. The court upheld warrantless arrests for minor offenses, like in Atwater's case, reaffirming lawful custodial arrests with probable cause.
    • 2.19: Chapter 20 - Stop and Frisk
      This page examines the "stop and frisk" tactic and its legal implications under the Fourth Amendment, focusing on the Supreme Court case Terry v. Ohio, which allows brief detentions based on reasonable suspicion. It discusses subsequent cases addressing searches of luggage and the duration of traffic stops, reaffirming the need for a balance between police authority and individual rights.
    • 2.20: Chapter 21 - Reasonable Suspicion
      This page reviews the Supreme Court's definition of "reasonable suspicion" in the context of police stops and frisks, highlighting varied judicial decisions and criticisms. Key cases such as Terry v. Ohio, United States v. Arvizu, and others illustrate how reasonable suspicion can arise from factors like unprovoked flight and anonymous tips. While some argue that current standards may infringe on individual rights, others believe they are essential for effective policing.

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