"Last November, we wrote about the case of Derek Heuring, an Indiana man the Warrick County Sheriff's Office suspected of selling meth. Authorities got a warrant to put a GPS tracker on Heuring's car, getting a stream of data on his location for six days. But then the data stopped."
"United States v. Jones, 565 U.S. 400 (2012), was a landmark United States Supreme Court case which held that installing a Global Positioning System (GPS) tracking device on a vehicle and using the device to monitor the vehicle's movements constitutes a search under the Fourth Amendment.[1]"
"In 2004 defendant Jones was suspected of drug trafficking. Police investigators asked for and received a warrant to attach a GPS tracking device to the underside of the defendant's car but then exceeded the warrant's scope in both geography and length of time. The Supreme Court justices voted unanimously that this was a "search" under the Fourth Amendment, although they were split 5-4 as to the fundamental reasons behind that conclusion. The majority held that by physically installing the GPS device on the defendant's car, the police had committed a trespass against Jones' "personal effects" – this trespass, in an attempt to obtain information, constituted a search per se."