The Fourth Amendment to the US Constitution states, “The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.”[i]
This amendment requires a warrant for arrests and to searches of persons, homes, and other private places. It thereby places a neutral magistrate between the police and citizens.[ii]
The Fourth Amendment to the US Constitution provides protection against unreasonable searches and seizures. The amendment specifically requires search and arrest warrants be judicially sanctioned and supported by probable cause. Searches and arrests must be limited in scope according to specific information supplied to the issuing court. That information is usually provided by a law enforcement officer who has sworn by it.
The Supreme Court has also ruled that certain searches and seizures violated the Fourth Amendment even when a warrant was properly granted. The Fourth Amendment specifies that, to be considered reasonable, all search and arrest warrants must be legally sanctioned. The Fourth Amendment only applies to governmental agencies. It does not guarantee a right to be free from unreasonable searches and seizures conducted by private citizens or organizations. Though, the Bill of Rights originally only restricted the power of the federal government, in Mapp v. Ohio[iv], the Supreme Court ruled that the Fourth Amendment is applicable to state governments by way of the Due Process Clause of the Fourteenth Amendment.
The reasonableness requirement of the Fourth Amendment applies not only to a search in combination with a seizure, but also to a search without a seizure, as well as to a seizure without a search. As a general rule, the government may not detain an individual even momentarily without reasonable suspicion. There are however a few exceptions to the rule of reasonableness. In cases when the need of the society is great and to effectively meet the needs of the society, if a minimal intrusion on people’s privacy is required; such intrusions can be made. In Michigan v. Sitz[v], the Supreme Court allowed sobriety checkpoints and in United States v. Martinez-Fuerte[vi]; the Supreme Court allowed immigration checkpoints.
While the Fourth Amendment does not apply to searches, seizures or arrests by private citizens, most states have state laws that regulate circumstances in which a private citizen may arrest another citizen. Generally, a person may arrest another if the latter commits a misdemeanor amounting to a public nuisance or a felony and the former has reasonable cause to believe that the person arrested committed it. However since arresting citizens are not protected by qualified immunity, if they are mistaken, they may face a civil lawsuit or charges of battery or false imprisonment.
Searches and seizures without a warrant are not considered unreasonable if one of the specifically established and well-delineated exceptions to the warrant requirement applies.
One way courts enforce the Fourth Amendment is with the exclusionary rule. The rule provides that evidence obtained through a violation of the Fourth Amendment is generally not admissible by the prosecution during a defendant’s criminal trial.
[i] http://www.archives.gov/exhibits/charters/bill_of_rights_transcript.html
[ii] http://www.senate.gov/civics/constitution_item/constitution.htm
[iii] 367 U.S. 643 (U.S. 1961)
[iv] 367 U.S. 643 (U.S. 1961)
[v] 496 U.S. 444 (U.S. 1990)
[vi] 428 U.S. 543 (U.S. 1976)