In a landmark ruling, the New York Court of Appeals – the state’s highest court – today ruled that police must get a warrant before using a GPS device to track a criminal subject. The New York Civil Liberties Union filed an amicus brief in the case.

“New York’s highest court has stood up for privacy and due process in the 21st Century,” said NYCLU Executive Director Donna Lieberman. “Placing a GPS device on a car is like allowing an invisible police officer to ride in the back seat. The court today rejected that practice without the oversight of a judge and probable cause.”

The decision came in People v. Weaver, in which Latham police investigating a series of burglaries had, without a warrant, attached a GPS device under the bumper of a suspect’s van while it was parked on a public street. The police then tracked the van’s movements for 65 days. Based on this tracking information and other evidence, the police charged the suspect with burglarizing the Latham Meat Market and the Latham K-Mart in 2005.

Last June, a state appeals court rejected the defendants’ claim that the warrantless use of a GPS device violated his state and federal constitutional rights. The appeals court said that that using a GPS is no different than an officer tailing a vehicle.

In an amicus curiae brief that it filed with the New York Court of Appeal, the NYCLU argued that 24-hour electronic tracking by the police poses an unprecedented threat to personal privacy that triggered the protections of the New York Constitution. In today’s decision, the Court of Appeals overturned the lower court and ruled that warrantless electronic tracking by the police violates the state constitution.

“This ruling firmly establishes that the police are not free to engage in unchecked surveillance of New Yorkers,” said NYCLU Associate Legal Director Christopher Dunn, who wrote the NYCLU’s amicus brief. “In an era of rapidly advancing surveillance technology, this is an extraordinarily important ruling.”

Also on the NYCLU’s brief were Legal Director Arthur Eisenberg and attorney Palyn Hung.