La Mesa’s automated license plate readers logged more than 3 million scans of license plates on the city’s 20 cameras during a seven-month span, from July 1, 2025, through Feb. 2.
The scans, according to data obtained and analyzed by Times of San Diego, show that on average, La Mesa’s license plate cameras were accessed every 3 to 6 seconds by law enforcement agencies throughout California.
To put it another way, the 20 cameras in the East San Diego County city on average logged 14,412 searches per day.
Over nine months, the number of searches conducted on ALPR cameras in the city of San Diego pales in comparison to La Mesa.
San Diego, which has 1.4 million residents, conducted 114,692 searches. Yet La Mesa, with nearly 60,000 residents, had over 3.13 million searches run through its cameras.
That number is so much larger because La Mesa isn’t the only agency searching through its ALPR network.
The city is part of a 306-entity shared network in California which includes cities, counties, fire departments, university police departments and probation agencies throughout the state.
“[These] reflect searches by outside agencies whose queries included La Mesa Police Department’s network among the networks searched,” said La Mesa Assistant City Manager Amanda Lee.
“A single search conducted by an outside agency may simultaneously query numerous participating Flock networks. Consequently, these figures do not necessarily represent searches specifically directed at La Mesa’s cameras or vehicles observed within the city.”
However, experts and social advocates say the vast network could lead to misuse and potential civil rights violations.
“That’s part of the reason why Flock has gotten the majority of the criticism, because of their ability to search cameras that are far away from your jurisdiction,” said John Shjarback, a criminology professor and ALPR researcher at Rowan University in Atlantic City, New Jersey.
Shjarback says part of Flock’s selling point to police departments is accessing hundreds, if not thousands, of cameras at once, much like what is happening in La Mesa.
“That’s the business model of Flock,” said Shjarback. “It’s like it’s a force multiplier in that not only do you subscribe to our cameras, you also have access to the vast array of Flock cameras available.”
Other cities, such as the city of San Diego, albeit after much prodding, opted out of Flock’s vast network, preventing outside agencies from accessing its license plate cameras.
And while outside agencies are nearly constantly accessing La Mesa’s license plate readers, La Mesa’s own officers use the 20 city cameras at a fraction of the greater rate.
According to city data, which reports in 30-day increments, La Mesa police conduct slightly more than six searches a day on average.
Lee, La Mesa’s assistant city manager, says the city does not control how often member networks access the city’s license plate readers.
“The frequency with which an authorized agency searches LMPD’s network is determined by that agency’s independent use of the Flock system,” said Lee. “Accordingly, a higher number of searches attributed to agencies in Riverside County or other parts of California does not indicate that (La Mesa Police Department) prioritizes sharing with those agencies over other local law enforcement partners.”
According to the network audit, the agencies most frequently tapping into La Mesa’s cameras and scanning drivers are outside of San Diego County.
More than 8% of the 3.13 million La Mesa searches from July 2025 through February were initiated by the California Highway Patrol. It was the top agency by far to access the city’s license plate readers, followed by Riverside County, with just under 8% of all searches.
Other agencies that also frequently tapped into the city’s surveillance tool during that period were the San Francisco police, followed by the Orange County Sheriff’s Department and the Los Angeles County Sheriff’s Department.
Among local law enforcement agencies, the San Diego County Sheriff’s Office accessed La Mesa’s readers a total of 57,879 times in the seven months. National City accessed the cameras 15,853 times, followed by Escondido at 12,390, Chula Vista, 11,303, El Cajon, 5,139, and Oceanside 4,589. The three remaining agencies in San Diego County — the Harbor Police, and departments in Coronado and Carlsbad — had 900 or fewer accesses.
Seth Hall has fought for years to regulate and improve the transparency of San Diego’s growing list of mass surveillance tools. He was integral in the San Diego City Council’s decision to opt out of Flock’s vast network.
Hall agrees that the instant access to a vast network of cameras is one of Flock’s main selling points. The problem is not so much other agencies searching La Mesa’s 20 license plate readers in statewide searches; it’s what the agencies choose to do with the data, and particularly, with whom it they share it.
“When Flock arrived in San Diego, the community was deeply concerned about the city allowing our data to be used by other agencies,” Hall said. “Gaining easy access to data from other agencies is Flock’s whole selling point. But the problem is that once our data is shared, nothing can prevent the shared data from ending up in the hands of federal agencies, which endangers people and also violates California law. So, to prevent that, you’d have to just not share data with anyone.”
Regarding the transparency of its license plate reader program, Lee, La Mesa’s assistant city manager, said the police department provides a “transparency portal” where members of the public can see the number of times La Mesa police initiated searches.
The portal, however, does not include the reasons for the searches, nor does it allow the public to download them.
As to requests for that information, according to Lee, “regarding whether the reasons entered for [Automated License Plate Reader] searches will be released, La Mesa Police will evaluate each California Public Records Act request individually, and nonexempt information will be released.”
