The Fourth Amendment to the United States Constitution is part of the Bill of Rights. It prohibits unreasonable searches and seizures. In addition, it sets requirements for issuing warrants: warrants must be issued by a judge or magistrate, justified by probable cause, supported by oath or affirmation, and must particularly describe the place to be searched and the persons or things to be seized.
Terry v. Ohio, 392 U.S. 1 (1968), was a landmark decision of the Supreme Court of the United States in which the Court ruled that it is not unconstitutional for American police to "stop and frisk" a person they reasonably suspect to be armed and involved in a crime. Specifically, the decision held that it is not a violation of the Fourth Amendment to the U.S. Constitution's prohibition on unreasonable searches and seizures when a police officer stops a suspect on the street and questions him or her even without probable cause to arrest, so long as the police officer has a reasonable suspicion that the person has committed, is committing, or is about to commit a crime. The Court also ruled that the police officer may perform a quick surface search of the person's outer clothing for weapons if they have reasonable suspicion that the person stopped is "armed and presently dangerous". This reasonable suspicion must be based on "specific and articulable facts", and not merely upon an officer's hunch.
False arrest is a common law tort, where a plaintiff alleges they were held in custody without probable cause, or without an order issued by a court of competent jurisdiction. Although it is possible to sue law enforcement officials for false arrest, the usual defendants in such cases are private security firms.
Weeks v. United States, 232 U.S. 383 (1914), was a United States Supreme Court case in which the Court unanimously held that the warrantless seizure of items from a private residence constitutes a violation of the Fourth Amendment. It also prevented local officers from securing evidence by means prohibited under the federal exclusionary rule and giving it to their federal colleagues. It was not until the case of Mapp v. Ohio, 367 U.S. 643 (1961), that the exclusionary rule was deemed to apply to state courts as well.
Castle Rock v. Gonzales, 545 U.S. 748 (2005), is a United States Supreme Court case in which the Court ruled, 7–2, that a town and its police department could not be sued under 42 U.S.C. § 1983 for failing to enforce a restraining order, which had led to the murder of a woman's three children by her estranged husband.
Atwater v. Lago Vista, 532 U.S. 318 (2001), was a United States Supreme Court decision which held that a person's Fourth Amendment rights are not violated when the subject is arrested for driving without a seatbelt. The court ruled that such an arrest for a misdemeanor that is punishable only by a fine does not constitute an unreasonable seizure under the Fourth Amendment.
In the United States, qualified immunity is a legal principle that grants government officials performing discretionary (optional) functions immunity from civil suits unless the plaintiff shows that the official violated "clearly established statutory or constitutional rights of which a reasonable person would have known". It is a form of sovereign immunity less strict than absolute immunity that is intended to protect officials who "make reasonable but mistaken judgments about open legal questions", extending to "all [officials] but the plainly incompetent or those who knowingly violate the law". Qualified immunity applies only to government officials in civil litigation, and does not protect the government itself from suits arising from officials' actions.
Brigham City v. Stuart, 547 U.S. 398 (2006), is a United States Supreme Court case involving the exigent circumstances exception to the Fourth Amendment's warrant requirement. The Court ruled that police may enter a home without a warrant if they have an objectively reasonable basis for believing that an occupant is or is about to be seriously injured.
Knowles v. Iowa, 525 U.S. 113 (1998), was a decision by the United States Supreme Court which ruled that the Fourth Amendment prohibits a police officer from further searching a vehicle which was stopped for a minor traffic offense once the officer has written a citation for the offense.
Monroe v. Pape, 365 U.S. 167 (1961), was a United States Supreme Court case that considered the application of federal civil rights law to constitutional violations by city employees. The case was significant because it held that 42 U.S.C. § 1983, a statutory provision from 1871, could be used to sue state officers who violated a plaintiff's constitutional rights. § 1983 had previously been a relatively obscure and little-used statute, but since Monroe it has become a central part of United States civil rights law.
Whren v. United States, 517 U.S. 806 (1996), was a unanimous United States Supreme Court decision that "declared that any traffic offense committed by a driver was a legitimate legal basis for a stop."
Maryland v. Buie, 494 U.S. 325 (1990), was a decision by the Supreme Court of the United States handed down in 1990. In the case, the Court held that the Fourth Amendment permits a properly limited protective sweep in conjunction with an in-home arrest when the searching officer possesses a reasonable belief based on specific and articulable facts that the area to be swept harbors an individual posing a danger to those on the arrest scene.
Ornelas v. United States, 517 U.S. 690 (1996), was a case decided by the Supreme Court of the United States that held that appellate courts should review probable cause determinations for warrantless searches de novo.
Glik v. Cunniffe, 655 F.3d 78 is a case in which the United States Court of Appeals for the First Circuit held that a private citizen has the right to record video and audio of police carrying out their duties in a public place, and that the arrest of the citizen for a wiretapping violation violated his First and Fourth Amendment rights. The case arose when Simon Glik filmed Boston, Massachusetts, police officers from the bicycle unit making an arrest in a public park. When the officers observed that Glik was recording the arrest, they arrested him and Glik was subsequently charged with wiretapping, disturbing the peace, and aiding in the escape of a prisoner. Glik then sued the City of Boston and the arresting officers, claiming that they violated his constitutional rights.
Steagald v. United States, 451 U.S. 204 (1981), is a United States Supreme Court case which held that, based on the Fourth Amendment, a police officer may not conduct a warrantless search of a third party's home in an attempt to apprehend the subject of an arrest warrant, absent consent or exigent circumstances.
Collins v. Virginia, No. 16-1027, 584 U.S. ___ (2018), was a case before the US Supreme Court involving search and seizure. At issue was whether the Fourth Amendment's motor vehicle exception permits a police officer uninvited and without a warrant to enter private property, approach a house, and search a vehicle parked a few feet from the house that is otherwise visible from off the property. In an 8–1 judgement, the Supreme Court ruled that the automobile exception does not apply to vehicles parked within the home or the curtilage of a private homeowner.
Nieves v. Bartlett, 587 U.S. ___ (2019), was a civil rights case in which the Supreme Court of the United States decided that probable cause should generally defeat a retaliatory arrest claim brought under the First Amendment, unless officers under the circumstances would typically exercise their discretion not to make an arrest.
Pierson v. Ray, 386 U.S. 547 (1967), was a United States Supreme Court case in which the Court first introduced the justification for qualified immunity for police officers from being sued for civil rights violations under Section 1983, by arguing that "[a] policeman's lot is not so unhappy that he must choose between being charged with dereliction of duty if he does not arrest when he had probable cause, and being mulcted in damages if he does."
Carroll v. United States, 354 U.S. 394 (1957), was a case dealing with the appealablility of a suppression order issued by the Federal District Court for the District of Columbia for an unlawful warrant under the Fourth Amendment.
Devenpeck v. Alford, 543 U.S. 146 (2004), was a United States Supreme Court decision dealing with warrantless arrests and the Fourth Amendment. The Court ruled that even if an officer wrongly arrests a suspect for one crime, the arrest may still be "reasonable" if there is objectively probable cause to believe that the suspect is involved in a different crime.
