Professor Orin Kerr made an interesting point over at The Volokh Conspiracy: the Supreme Court did not explicitly state that police officers need a warrant to attach a GPS device to a car. On Monday’s post I said that police will need a warrant, but the Court’s decision stops short of stating that. The Court said that the GPS device constituted a “search,” which generally requires a warrant, but there are so many exceptions to that rule that lawyers frequently get them mixed-up.

However, in practicality, the police really will need a warrant. Neither prosecutors nor police officers are going to risk losing otherwise good evidence just to test the state of the law. It may be a few years before the Court resolves this issue definitively.