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.
A search warrant is a court order that a magistrate or judge issues to authorize law enforcement officers to conduct a search of a person, location, or vehicle for evidence of a crime and to confiscate any evidence they find. In most countries, a search warrant cannot be issued in aid of civil process.
In United States criminal law, probable cause is the standard by which police authorities have reason to obtain a warrant for the arrest of a suspected criminal or the issuing of a search warrant. There is no universally accepted definition or formulation for probable cause. One traditional definition, which comes from the U.S. Supreme Court's 1964 decision Beck v. Ohio, is when "whether at [the moment of arrest] the facts and circumstances within [an officer's] knowledge and of which they had reasonably trustworthy information [are] sufficient to warrant a prudent [person] in believing that [a suspect] had committed or was committing an offense."
Terry v. Ohio, 392 U.S. 1 (1968), was a landmark U.S. Supreme Court decision in which the Court ruled that it is constitutional 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 a police officer does not violate the Fourth Amendment to the U.S. Constitution's prohibition on unreasonable searches and seizures when questioning someone even though the officer lacks probable cause to arrest the person, 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.
A traffic stop, commonly referred to as being pulled over, is a temporary detention of a driver of a vehicle and its occupants by police to investigate a possible crime or minor violation of law.
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.
Chimel v. California, 395 U.S. 752 (1969), was a 1969 United States Supreme Court case in which the Court held that police officers arresting a person at home could not search the entire home without a search warrant, but police may search the area within immediate reach of the person without a warrant. The rule on searches incident to a lawful arrest within the home is now known as the Chimel Rule.
Search incident to a lawful arrest, commonly known as search incident to arrest (SITA) or the Chimel rule, is a U.S. legal principle that allows police to perform a warrantless search of an arrested person, and the area within the arrestee’s immediate control, in the interest of officer safety, the prevention of escape, and the preservation of evidence.
Ker v. California, 374 U.S. 23 (1963), was a case before the United States Supreme Court, which incorporated the Fourth Amendment's protections against illegal search and seizure. The case was decided on June 10, 1963, by a vote of 5–4.
California v. Acevedo, 500 U.S. 565 (1991), was a decision of the United States Supreme Court, which interpreted the Carroll doctrine to provide one rule to govern all automobile searches. The Court stated, "The police may search an automobile and the containers within it where they have probable cause to believe contraband or evidence is contained." The decision also overruled the distinctions in United States v. Chadwick (1977) and Arkansas v. Sanders (1979) which had previously held that, if probable cause existed to search an automobile, the police may perform a warrantless search of the automobile and the containers within it, but if the police only had probable cause to search a container in the automobile, the police first had to obtain a warrant before searching the container.
Carroll v. United States, 267 U.S. 132 (1925), was a decision by the United States Supreme Court that upheld the warrantless searches of an automobile, which is known as the automobile exception. The case has also been cited as widening the scope of search.
Wilson v. Arkansas, 514 U.S. 927 (1995), is a United States Supreme Court decision in which the Court held that the traditional, common-law-derived "knock and announce" rule for executing search warrants must be incorporated into the "reasonableness" analysis of whether the actual execution of the warrant is/was justified under the 4th Amendment. The high court thus ruled that the old "knock and announce" rule while not a hard requirement, was also not a dead letter.
Arizona v. Gant, 556 U.S. 332 (2009), was a United States Supreme Court decision holding that the Fourth Amendment to the United States Constitution requires law enforcement officers to demonstrate an actual and continuing threat to their safety posed by an arrestee, or a need to preserve evidence related to the crime of arrest from tampering by the arrestee, in order to justify a warrantless vehicular search incident to arrest conducted after the vehicle's recent occupants have been arrested and secured.
New York v. Belton, 453 U.S. 454 (1981), was a United States Supreme Court case in which the Court held that when a police officer has made a lawful custodial arrest of the occupant of an automobile, the officer may, as a contemporaneous incident of that arrest, search the passenger compartment of that automobile. Therefore, Belton extended the so-called "Chimel rule" of searches incident to a lawful arrest, established in Chimel v. California (1969), to vehicles. The Supreme Court sought to establish bright line rules to govern vehicle search incident to eliminate some confusion in the cases.
United States v. Robinson, 414 U.S. 218 (1973), was a case in which the United States Supreme Court held that "in the case of a lawful custodial arrest a full search of the person is not only an exception to the warrant requirement of the Fourth Amendment, but is also a reasonable search under that Amendment."
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.
Cupp v. Murphy, 412 U.S. 291 (1973), was a United States Supreme Court case in which the Court upheld a murder conviction notwithstanding a challenge that the evidence upon which guilt was based was obtained in violation of the Fourth and Fourteenth Amendments of the United States Constitution. The court held that in view of the station-house detention upon probable cause, the very limited intrusion of scraping the defendant's fingernails for blood and other material, undertaken to preserve highly evanescent evidence, did not violate the Fourth and Fourteenth Amendments.
Florida v. Thomas, 532 U.S. 774 (2001), is a United States Supreme Court case decided in 2001. The case brought to the court concerned the extent of the Court's earlier decision in New York v. Belton, concerning whether a person was in custody, a determination central to allowing evidence seized in an automobile search to be presented in trial. However, the Court unanimously dismissed the case because the decision of the Florida state courts was not "final".
Kentucky v. King, 563 U.S. 452 (2011), was a decision by the US Supreme Court, which held that warrantless searches conducted in police-created exigent circumstances do not violate the Fourth Amendment as long as the police did not create the exigency by violating or threatening to violate the Fourth Amendment.
Riley v. California, 573 U.S. 373 (2014), is a landmark United States Supreme Court case in which the court ruled that the warrantless search and seizure of the digital contents of a cell phone during an arrest is unconstitutional under the Fourth Amendment.
