Last January, the US Supreme Court ruled that the police must obtain a warrant before secretly attaching a GPS tracking device to your car, at least for any length of time. The decision in Jones v. United States was heralded as a small victory for those of us who like our gadgets but love our privacy even more.

Yesterday, the US Circuit Court of Appeals for the Sixth Circuit failed to uphold the same kind of privacy protection for cell phones. In United States v. Skinner it ruled that because we all know cell phones have GPS transponders that can broadcast our locations at any time, we have no reasonable expectation of privacy when we carry them.