A California police department searched AI-enabled, automatic license plate reader (ALPR) cameras in relation to an “immigration protest,” according to internal police data obtained by 404 Media. The data also shows that police departments and sheriff offices around the country have repeatedly tapped into the cameras inside California, made by a company called Flock, on behalf of Immigration and Customs Enforcement (ICE), digitally reaching into the sanctuary state in a data sharing practice that experts say is illegal. 

Flock allows participating agencies to search not only cameras in their jurisdiction or state, but nationwide, meaning that local police that may work directly with ICE on immigration enforcement are able to search cameras inside California or other states. But this data sharing is only possible because California agencies have opted-in to sharing it with agencies in other states, making them legally responsible for the data sharing. 

The news raises questions about whether California agencies are enforcing the law on their own data sharing practices, threatens to undermine the state’s perception as a sanctuary state, and highlights the sort of surveillance or investigative tools law enforcement may deploy at immigration related protests. Over the weekend, millions of people attended No Kings protests across the U.S. 404 Media’s findings come after we revealed police were searching cameras in Illinois on behalf of ICE, and then Cal Matters found local law enforcement agencies in California were searching cameras for ICE too.

“I think especially in this current political climate where the government is taking extreme measures to crack down on civil liberties, especially immigrants’ rights being one of those, you can easily see how ALPRs, which is an extremely invasive technology, could be weaponized against that community,” Jennifer Pinsof, a senior staff attorney at activist organization the Electronic Frontier Foundation (EFF), told 404 Media.

404 Media obtained the data through a public records request with Redlands Police Department in California. The collection of spreadsheets comprises the agency’s “Network Audit” of what other agencies have searched using its Flock systems since June 1, 2024 and the reason the agency provided for doing so. 

The data shows that on February 3, the Escondido Police Department in California searched Flock cameras for an “immigration protest.” Days earlier the police department said it impounded 11 cars that blocked traffic and endangered the public. “The Escondido Police Department and our law enforcement partners are committed to protecting the rights of individuals to express their views peacefully,” Erik Witholt, the interim Escondido police chief, said, the San Diego Union-Tribune reported. “However, when drivers choose to block roadways, occupy intersections and commit other acts that pose a clear and present danger to attendees and the public, we will act to restore order and safety,” Witholt said. 

“As a First Amendment lawyer I find that to be particularly concerning because ALPRs can obviously be used to identify who’s driving towards, away from, parking near, and therefore being a part of attending a protest,” Pinsof said. “You can see how just the presence of such dragnet surveillance can chill people’s willingness to speak out publicly or attend protests in causes that we believe in. And I think it’s especially wrong in moments like now where the government is taking extreme measures to crack down on civil liberties of protesters specifically.”

Other examples in the data include:

• On February 7, the Raleigh Police Department in North Carolina searched Redlands’ and other agencies’ cameras, looking for hits over a one month period. The reason given was “ICE.” That search was across 75,819 cameras and 6,264 networks according to the data, indicating it was likely a national search not limited to just Redlands.
• On January 29, Nolensville Police Department in Tennessee performed a search of Redlands’ cameras for “ICE.”
• Lowndes County Sheriff’s Office in Georgia repeatedly searched Redlands’ Flock cameras, with the reason given as “ICE,” according to the data.

Those searches took place alongside the Trump administration’s ongoing mass deportation efforts, with ICE tasked with arresting a quota of at least 3,000 people a day. But searches of Flock cameras in California by other agencies repeatedly occurred during the Biden administration too, the data shows, including others from Lowndes County Sheriff’s Office.

Flock is a popular ALPR system with a presence in thousands of communities around the U.S. These cameras constantly record the license plates, color, and model of vehicles driving by, creating a timestamped record of a vehicle’s, and by extension a person’s, movements. Law enforcement typically conducts searches of Flock to see where a vehicle travelled without a warrant, something that an ongoing lawsuit argues is unconstitutional. 

A Flock user guide explains that its national lookups feature allows “all law enforcement agencies across the country” who are also opted into the setting to search a user’s cameras. After 404 Media first revealed local law enforcement agencies were performing lookups for ICE, and that a cop in Texas searched Flock cameras nationwide for a woman who had a self-administered abortion, Flock made radical changes to its data sharing system, including cutting off agencies that were searching cameras in Illinois that didn’t comply with state law. 

A search reason being listed as ICE does not necessarily mean it was related to immigration enforcement. ICE and its Homeland Security Investigations (HSI) division has a wide mandate to investigate crimes such as child abuse or money launderering. 

But the data sharing is still illegal, according to Pinsof. Specifically, it violates SB 34, a law California passed ten years ago. “The language of SB 34 is that a public agency shall not sell, share, or transfer ALPR information,” she said. “And so it’s illegal for Georgia just to have access to that information full stop. It doesn’t matter what the reason is.” The EFF previously found dozens of California agencies were sharing ALPR data with other states. 

404 Media’s original May investigation into ICE tapping into Flock’s system was based on data obtained through public records requests by researchers who asked to remain anonymous. 404 Media provided links to the underlying dataset. 404 Media then filed dozens of its own public records requests with agencies inside California. In the wake of that article, many other locally-focused media outlets across the U.S. have used the data for their own stories, filed their own requests, or published articles based on similar data provided to them.  

Last week Cal Matters reported that California police were illegally sharing license plate data with ICE and Border Patrol. That article was based on data provided by anti-surveillance group Oakland Privacy and found agencies such as the LAPD and sheriff’s departments in San Diego and Orange counties searched Flock systems on behalf of ICE. It differs slightly in that it was focused on Californian agencies sharing data with ICE more directly, whereas 404 Media’s data shows local police in other parts of the country reaching into California on behalf of ICE. 

The Redlands Police Department, Lowndes County Sheriff’s Office, and the City of Escondido did not respond to a request for comment. Flock declined to comment.

About the author

Joseph is an award-winning investigative journalist focused on generating impact. His work has triggered hundreds of millions of dollars worth of fines, shut down tech companies, and much more.