Four California law enforcement agencies have not provided enough privacy protections for hundreds of millions of images collected by automated license plate readers, a recent state audit said.
Nearly every local law enforcement agency in San Diego County uses the automated license plate readers, although none were audited in this report.
Law enforcement agencies say license plate readers save time and help solve crimes, but others cite privacy concerns, including data breaches.
An automated license plate reader can be mounted at intersections or on patrol cars. It scans license plates to figure out if a vehicle is connected to a crime. The images are then stored in databases.
A recent state audit looked closely at the Fresno and Los Angeles police department and the Marin and Sacramento County Sheriff's offices.
It found concerns with the way those agencies are storing images on third party servers and distributing those images.
NBC 7 Investigates
Dave Maas with the Electronic Frontier Foundation has been raising concerns about license plate readers since 2012.
"What the auditor found was that none of the four agencies were doing audits," Maas said. "They were not controlling access to the system in a responsible way or keeping track of who is searching it. And all of this is dangerous if it's being abused against us, it's not as if we would even know because the police aren't keeping track."
State Auditor Elaine Howle says changes are needed to better safeguard people's privacy.
Howle recommended the state Department of Justice develop a policy to protect privacy, that could be adopted by local law enforcement agencies. She also said there needed to be better oversight, to make sure agencies were complying with those policies.
"Really one of the things they need to do is start following the law," said Maas. "But that isn't enough. The law needs to be revised. We want to see the state really reign in this technology, reign in how long they are able to keep the data, reign in who they are allowed to share it with."
The San Diego Police Department has 27 license plate readers attached to police vehicles.
A police spokesperson told NBC 7 Investigates that although they were not highlighted in the state audit, they are looking at the report to ensure they are following the best practices and "ensuring our policy meets guidelines."
According to the Electronic Frontier Foundation, in 2019 the San Diego Sheriff's Department scanned 7,086,646 plates. 2,825 were on a "hot list," meaning only .04 percent of those plates were under suspicion at the time the data was collected.
If you live in California and want to find information about license plate readers in your area. Find the map here.