United States v. Jones

The Court recognized that the “Fourth Amendment provides in relevant part that ‘[t]he right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated.’ It is beyond dispute that a vehicle is an ‘effect’ as that term is used in the Amendment.” “The Government physically occupied private property for the purpose of obtaining information. We have no doubt that such a physical intrusion would have been considered a ‘search’ within the meaning of the Fourth Amendment when it was adopted.” This definition of a “search” [government trespass on “persons, houses, papers and effects” for the purpose of obtaining information] is considered a supplement to and not a replacement of the well-recognized formula of the Katz case [government intrusion on a reasonable expectation of privacy].