A U.S. appeals court in Philadelphia has ruled that police can't routinely put GPS devices on vehicles without search warrants.
The ruling last month comes a year after the U.S. Supreme Court said GPS tracking constitutes a police search—but didn't say if police need warrants to use them.
Police put a GPS device under their bumper of three brothers suspected in a series of pharmacy robberies, and soon tracked them to another burglary. They found pills and other property from the pharmacy in the van.
But a federal judge threw out that evidence, and the appeals court agreed.
The American Civil Liberties Union says it would be easy for police to abuse the practice, because the devices are so cheap. The Justice Department is considering an appeal.
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