An Idaho Court of Appeals has refused to hold that a warrant is required for the use of a GPS tracking device.
The case is State v. Danney. The police suspected that the defendant was involved in marijuana trafficking. The police placed a GPS tracking device on his vehicle when it was parked outside his business. Using the device, they tracked the vehicle making a trip to California, and then initiated a traffic stop when it returned to Idaho. a drug dog alerted on the vehcile, and a subsequent search revealed marijuana.
Because the defendant did not raise the issue of the constitutionality of the use of a GPS device in the trial court, his conviction could be overturned only if the use of the device was a fundamental error. The court concluded it was not because "To the extent that it has been addressed, the jurisprudence in this area is conflicting." The court then cites to a number of opinions both permitting and prohibiting the warrantless use of the devices.