Judge rules warrantless Flock search broke the Fourth Amendment

A federal judge in Oklahoma has ruled that a sheriff's deputy violated a woman's Fourth Amendment rights when he searched her licence plate in Flock Safety's automated plate-reading network without a warrant. Judge Sara Hill's opinion, issued on 1 October in the Northern District of Oklahoma, found that the search “was not supported by probable cause, and it was done without a warrant”.

How the case unfolded

A Tulsa County deputy, Freddie Alaniz, was parked beside a highway in May when a Mazda SUV with a California plate passed him. He followed it, later saying he had no reason beyond the out-of-state plate, and queried the plate through Flock. He then stopped the driver, Melisa Kyle, and questioned her about her movements while checking the plate-reading records against her account. Hill noted that the single query returned more than 50 individual records of her whereabouts across a month. The deputy used that travel history as part of his justification for searching the vehicle, where 91 pounds of methamphetamine was found. Hill suppressed all of it.

Why the ruling matters

The decision does not bind other courts, and several cases weighing warrantless plate-reader searches are still working through the system. What makes it notable is the reasoning. Hill rejected the argument that tracking vehicles in public is harmless, writing that cataloguing a person's movements indiscriminately over an extended period, then holding the data for use whenever convenient, is “a type of indiscriminate mass surveillance”. She contrasted it with the Supreme Court's Carpenter ruling on mobile phone location data, noting that a plate-reader network sweeps up every vehicle passing a networked camera rather than targeting one person. 404 Media reported, from audit logs it reviewed, that more than a hundred thousand warrantless searches of Flock's system take place every month.

The wider backlash

Hill's opinion lands amid mounting resistance to the company. Florida and Texas have moved to restrict the cameras, Senator Bernie Sanders has introduced the Block Flock Act to bar federal agencies from using automated plate readers, and Flock's chief executive, Garrett Langley, has publicly called for a “compromise” between privacy and safety. The company has also reportedly offered voluntary buyouts as it looks to shrink its workforce.

Our opinion

The heart of Hill's opinion is not the suppression order, which is the routine consequence of a warrantless search, but the line she draws around scale. Plate readers have been defended for a decade on the grounds that a licence plate in traffic is public, and her answer is that the objection was never to a single sighting. It is to a private company accumulating a national movement history and handing it to police on demand, which is a far harder thing to describe as incidental. That reasoning travels well, and it is why other courts are likely to reach for it. Flock's commercial problem is that the audit logs proving the system's usefulness also document its reach: a hundred thousand warrantless searches a month is not a narrow tool. The company can argue for compromise, but compromise is what courts exist to define.