The Fourth Circuit Court of Appeals, in upholding a firearms conviction, has held that police in Baltimore acted in good faith when using a tracking device without a warrant to follow the movement of a suspect:

In 2011, the police installed the battery-operated Global Positioning System device under the rear bumper of a vehicle parked in a public lot in suburban Baltimore. Officers used visual surveillance and the GPS tracker to find and stop the driver, Henry Stephens, the target of a gun and drug investigation. The police found a loaded pistol in Stephens’ vehicle.

Stephens pleaded guilty but kept alive his challenge of the admission of the evidence in the case. The installation of the device occurred before the U.S. Supreme Court, in January 2012, ruled in United States v. Jones that the warrantless use of a tracking device was a “search” under the Fourth Amendment that implicated privacy rights.

“The court did not, however, rule that all warrantless GPS searches violate the Fourth Amendment; instead, the court expressly declined to decide whether reasonable suspicion or probable cause may justify warrantless GPS attachment to vehicles, and that remains an open question,” Judge Dennis Shedd of the Fourth Circuit wrote for the majority.

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