For the first time, a federal court has held that a police officer’s use of an automated license plate reader (ALPR) system violated the Fourth Amendment. The U.S. District Court for the Northern District of Oklahoma issued its ruling Thursday in the drug-trafficking case United States v. Kyle. The case arose when a Tulsa County deputy used Flock ALPR data to learn that an SUV that passed him had recently completed a short trip to the California-Arizona border area.

The district court granted the driver’s motion to suppress the evidence against her, holding that the Fourth Amendment keeps the government from monitoring “where everyone goes all the time.” Matthew Cavedon, Director of the Project on Criminal Justice at the Cato Institute, welcomed the ruling:

Americans should not be caught in government-surveillance dragnets every time they venture outside. The Fourth Amendment is meant to prevent Panopticon, and it’s heartening to have precedent insisting that the Constitution keeps pace with the threats posed by new technology like ALPRs.”

To speak with Cavedon regarding ALPRs, Flock, and other technology-based threats to privacy, contact Cato PR at pr@​cato.​org.