It’s no secret that 2025 has given Americans plenty to protest about. But as news cameras showed protesters filling streets of cities across the country, law enforcement officers—including U.S. Border Patrol agents—were quietly watching those same streets through different lenses: Flock Safety automated license plate readers (ALPRs) that tracked every passing car.
Through an analysis of 10 months of nationwide searches on Flock Safety’s servers, we discovered that more than 50 federal, state, and local agencies ran hundreds of searches through Flock’s national network of surveillance data in connection with protest activity. In some cases, law enforcement specifically targeted known activist groups, demonstrating how mass surveillance technology increasingly threatens our freedom to demonstrate.
Flock Safety provides ALPR technology to thousands of law enforcement agencies. The company installs cameras throughout their jurisdictions, and these cameras photograph every car that passes, documenting the license plate, color, make, model and other distinguishing characteristics. This data is paired with time and location, and uploaded to a massive searchable database. Flock Safety encourages agencies to share the data they collect broadly with other agencies across the country. It is common for an agency to search thousands of networks nationwide even when they don’t have reason to believe a targeted vehicle left the region.
Via public records requests, EFF obtained datasets representing more than 12 million searches logged by more than 3,900 agencies between December 2024 and October 2025. The data shows that agencies logged hundreds of searches related to the 50501 protests in February, the Hands Off protests in April, the No Kings protests in June and October, and other protests in between.
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While EFF and other civil liberties groups argue the law should require a search warrant for such searches, police are simply prompted to enter text into a “reason” field in the Flock Safety system. Usually this is only a few words–or even just one.
In these cases, that word was often just “protest.”
Crime does sometimes occur at protests, whether that’s property damage, pick-pocketing, or clashes between groups on opposite sides of a protest. Some of these searches may have been tied to an actual crime that occurred, even though in most cases officers did not articulate a criminal offense when running the search. But the truth is, the only reason an officer is able to even search for a suspect at a protest is because ALPRs collected data on every single person who attended the protest.
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In a few cases, police were using Flock’s ALPR network to investigate threats made against attendees or incidents where motorists opposed to the protests drove their vehicle into crowds. For example, throughout June 2025, an Arizona Department of Public Safety officer logged three searches for “no kings rock threat,” and a Wichita (Kan.) Police Department officer logged 22 searches for various license plates under the reason “Crime Stoppers Tip of causing harm during protests.”
Even when law enforcement is specifically looking for vehicles engaged in potentially criminal behavior such as threatening protesters, it cannot be ignored that mass surveillance systems work by collecting data on everyone driving to or near a protest—not just those under suspicion.
Border Patrol’s Expanding Reach
As U.S. Border Patrol (USBP), ICE, and other federal agencies tasked with immigration enforcement have massively expanded operations into major cities, advocates for immigrants have responded through organized rallies, rapid-response confrontations, and extended presences at federal facilities.
USBP has made extensive use of Flock Safety’s system for immigration enforcement, but also to target those who object to its tactics. In June, a few days after the No Kings Protest, USBP ran three searches for a vehicle using the descriptor “Portland Riots.”
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Fighting Back Against ALPR
ALPR systems are designed to capture information on every vehicle that passes within view. That means they don’t just capture data on “criminals” but on everyone, all the time—and that includes people engaged in their First Amendment right to publicly dissent. Police are sitting on massive troves of data that can reveal who attended a protest, and this data shows they are not afraid to use it.
Our analysis only includes data where agencies explicitly mentioned protests or related terms in the “reason” field when documenting their search. It’s likely that scores more were conducted under less obvious pretexts and search reasons. According to our analysis, approximately 20 percent of all searches we reviewed listed vague language like “investigation,” “suspect,” and “query” in the reason field. Those terms could well be cover for spying on a protest, an abortion prosecution, or an officer stalking a spouse, and no one would be the wiser–including the agencies whose data was searched. Flock has said it will now require officers to select a specific crime under investigation, but that can and will also be used to obfuscate dubious searches.
For protestors, this data should serve as confirmation that ALPR surveillance has been and will be used to target activities protected by the First Amendment. Depending on your threat model, this means you should think carefully about how you arrive at protests, and explore options such as by biking, walking, carpooling, taking public transportation, or simply parking a little further away from the action. Our Surveillance Self-Defense project has more information on steps you could take to protect your privacy when traveling to and attending a protest.
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Everyone should have the right to speak up against injustice without ending up in a database.
Source: How Cops Are Using Flock Safety’s ALPR Network To Surveil Protesters And Activists | Techdirt
