On January 23, 2012, the U.S. Supreme Court issued its ruling in the landmark United States v. Jones case, holding 9-0 that attaching a GPS device to a suspect’s car to monitor the vehicle’s movements constitutes a Fourth Amendment search that requires a warrant.  Writing for the Court, Justice Scalia found that it was not necessary to determine whether Jones had a “reasonable expectation of privacy” in the underbody of his Jeep parked on a public street because the search violated the Court’s traditional common-law trespass test.  Scalia stated:

“It is important to be clear about what occurred in this case: 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.”

We reported on U.S. v. Jones in November of last year, when the Supreme Court heard oral arguments in the case.