The Fourth Amendment to the United States Constitution is part of the Bill of Rights. It prohibits unreasonable searches and seizures and 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."
Concealment devices or diversion safes are used to hide things for the purpose of secrecy or security. They are made from an ordinary household object such as a book, a soda can, a candle, a can, or something as small as a coin. The idea is that such an inconspicuous object would not be expected to contain anything of worth.
United States v. Ross, 456 U.S. 798 (1982), was a search and seizure case argued before the Supreme Court of the United States. The high court was asked to decide if a legal warrantless search of an automobile allows closed containers found in the vehicle to be searched as well. The appeals court had previously ruled that opening and searching the closed portable containers without a warrant was a violation of the Fourth Amendment, even though the warrantless vehicle search was permissible due to existing precedent.
Reasonable suspicion is a legal standard of proof in United States law that is less than probable cause, the legal standard for arrests and warrants, but more than an "inchoate and unparticularized suspicion or 'hunch'"; it must be based on "specific and articulable facts", "taken together with rational inferences from those facts", and the suspicion must be associated with the specific individual. If police additionally have reasonable suspicion that a person so detained is armed and dangerous, they may "frisk" the person for weapons, but not for contraband like drugs. However, if the police develop probable cause during a weapons frisk, they may then conduct a full search. Reasonable suspicion is evaluated using the "reasonable person" or "reasonable officer" standard, in which said person in the same circumstances could reasonably suspect a person has been, is, or is about to be engaged in criminal activity; it depends upon the totality of circumstances, and can result from a combination of particular facts, even if each is individually innocuous.
In the United States, the plain view doctrine is an exception to the Fourth Amendment's warrant requirement that allows an officer to seize evidence and contraband that are found in plain view during a lawful observation. The doctrine is also regularly used by Transportation Security Administration (TSA) officers while screening persons and property at U.S. airports.
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 his home could not search the entire home without a search warrant, but that 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.
South Dakota v. Opperman, 428 U.S. 364 (1976), elaborated on the community caretaking doctrine. Under the Fourth Amendment, "unreasonable" searches and seizures are forbidden. In addition to their law-enforcement duties, the police must engage in what the court has termed a community caretaking role, including such duties as removing obstructions from roadways to ensure the free flow of traffic. When the police act in this role, they may inventory cars they have seized without "unreasonably" searching those cars.
Frisking is a search of a person's outer clothing wherein a person runs their hands along the outer garments of another to detect any concealed weapons or objects.
Arizona v. Hicks, 480 U.S. 321 (1987), held that the Fourth Amendment requires the police to have probable cause to seize items in plain view.
Police officers in various jurisdictions have power to search members of the public, for example, for weapons, drugs and stolen property. This article concerns searches of members of the public who have not been arrested and who are not held in detention. For search powers in relation to those persons see Search on arrest and Searches in detention. For searches of property, rather than people, see search and seizure.
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.
Wyoming v. Houghton, 526 U.S. 295 (1999), is a United States Supreme Court case which held that absent exigency, the warrantless search of a passenger's container capable of holding the object of a search for which there is probable cause is not a violation of the Fourth Amendment to the United States Constitution because it is justified under the automobile exception as an effect of the car.
Horton v. California, 496 U.S. 128 (1990), was a United States Supreme Court case in which the Court held that the Fourth Amendment does not prohibit the warrantless seizure of evidence which is in plain view. The discovery of the evidence does not have to be inadvertent, although that is a characteristic of most legitimate plain-view seizures. The opinion clarified the plain view doctrine of the Court's Fourth Amendment analysis.
The powers of the police in Scotland, as with much of Scots law, are based on mixed elements of statute law and common law.
The powers of the police in England and Wales are defined largely by statute law, with the main sources of power being the Police and Criminal Evidence Act 1984 and the Police Act 1996. This article covers the powers of police officers of territorial police forces only, but a police officer in one of the UK's special police forces can utilise extended jurisdiction powers outside of their normal jurisdiction in certain defined situations as set out in statute. In law, police powers are given to constables. All police officers in England and Wales are "constables" in law whatever their rank. Certain police powers are also available to a limited extent to police community support officers and other non warranted positions such as police civilian investigators or designated detention officers employed by some police forces even though they are not constables.
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.
People v. Diaz, 51 Cal. 4th 84, 244 P.3d 501, 119 Cal. Rptr. 3d 105 was a Supreme Court of California case, which held that police are not required to obtain a warrant to search information contained within a cell phone in a lawful arrest. In a sting operation conducted by local police, the defendant, Gregory Diaz, was arrested for the sale of the illicit drug ecstasy and his cellphone, containing incriminating evidence, was seized and searched without a warrant. In trial court proceedings, Diaz motioned to suppress the information obtained from his cellphone, which was denied on the grounds that the search of his cellphone was incident to a lawful arrest. The California Court of Appeal affirmed the court's decision and was later upheld by the California Supreme Court. In 2014, the United States Supreme Court overruled that position in Riley v. California and held that without a warrant, police may not search the digital information on a cellphone that has been seized incident to arrest.
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.
