The attachment of a global positioning system (GPS) tracking device to an individual's vehicle and subsequent monitoring of the GPS constitutes a Fourth Amendment search. Applying 18th-century trespass law, a vehicle is an "effect" as the term is used in the Fourth Amendment, and the physical intrusion would have been a search within the meaning of the Amendment at the time it was adopted. The Court does not reach the question of reasonableness of the search because it was not raised below. 

United States v. Jones
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