A federal appeals court ruled Tuesday that police need a warrant based on probable cause to attach a GPS device to a suspect's car.
The Supreme Court ruled last year that attaching a GPS device to a car qualifies as a "search" under the Fourth Amendment, but the justices stopped short of declaring that police need a warrant.
The Third Circuit Court of Appeals held Tuesday in a two-to-one decision that attaching a GPS device to a car without a warrant is an "unreasonable search," and therefore unconstitutional.
The court rejected a series of arguments by the government that the GPS tracking should fall under established exceptions to the warrant requirement, and threw out any evidence collected as result of the GPS device.
"Today's decision is a victory for all Americans because it ensures that the police cannot use powerful tracking technology without court supervision and a good reason to believe it will turn up evidence of wrongdoing," said American Civil Liberties Union Staff Attorney Catherine Crump, who argued the case before the court. "These protections are important because where people go reveals a great deal about them, from who their friends and business associates are to what doctors they go to."
In a dissent, Judge Franklin Van Antwerpen agreed that police need a warrant to install a GPS device, but he argued that the court should have allowed the evidence to be used against Katzin in court.