Amendment IV
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.
The Fourth Amendment (Amendment IV) to the United States Constitution is the part of the Bill of Rights that prohibits unreasonable searches and seizures and requires any warrant to be judicially sanctioned and supported by probable cause. It was adopted in response to the abuse of the writ of assistance, a type of general search warrant issued by the British government and a major source of tension in pre-Revolutionary America. The Fourth Amendment was introduced in Congress in 1789 by James Madison, along with the other amendments in the Bill of Rights, in response to Anti-Federalist objections to the new Constitution. Congress submitted the amendment to the states on September 28, 1789. By December 15, 1791, the necessary three-quarters of the states had ratified it. On March 1, 1792, Secretary of State Thomas Jefferson announced the adoption of the amendment.
Because the Bill of Rights did not initially apply to the states, and federal criminal investigations were less common in the first century of the nation's history, there is little significant case law for the Fourth Amendment before the 20th century. The amendment was held to apply to the states in Mapp v. Ohio (1961).
Under the Fourth Amendment, search and seizure (including arrest) should be limited in scope according to specific information supplied to the issuing court, usually by a law enforcement officer who has sworn by it. Fourth Amendment case law deals with three central questions: what government activities constitute "search" and "seizure"; what