Police departments across the country searched records from a national network of automated license plate reader cameras hundreds of times over the last year to track protest activity, according to new research from the Electronic Frontier Foundation (EFF). 

EFF analyzed 10 months of nationwide searches on servers from Flock Safety, a controversial provider of surveillance technology, and found that more than 50 federal, state and local agencies ran protest-related searches, including queries about the “No Kings” demonstrations held in June and October. Law enforcement in some cases homed in on specific activist groups, EFF said. 

The analyzed data spans from last December to October 2025.

In addition to searches related to the “No Kings” protests, researchers found law enforcement searched for license plates present at other protests opposing the Trump administration, including demonstrations connected to the 50501 movement in February, and the “Hands Off!” protests in April.

EFF’s research was first reported by 404 Media.

Flock has been losing police department customers in recent months as reports of law enforcement using the company’s tools to track undocumented immigrants, as well as a woman who had an abortion, have surfaced.

On Wednesday, a police chief in suburban Atlanta was reportedly arrested for stalking citizens based on information gleaned from his city’s automated license plate camera network. It is unclear if those cameras were part of the Flock network or were deployed by another vendor.

A spokesperson for Flock Safety did not immediately respond to a request for comment.