Lawsuit Challenges San Jose’s Warrantless ALPR Mass Surveillance

Contact: Josh Richman, EFF, jrichman@eff.org;  Carmen King, ACLU of Northern California, cking@aclunc.org

SAN JOSE, Calif. – San Jose and its police department routinely violate the California Constitution by conducting warrantless searches of the stored records of millions of drivers’ private habits, movements, and associations, the Electronic Frontier Foundation (EFF) and American Civil Liberties Union of Northern California (ACLU-NC) argue in a lawsuit filed Tuesday. 

The lawsuit, filed in Santa Clara County Superior Court on behalf of the Services, Immigrant Rights and Education Network (SIREN) and the Council on American-Islamic Relations – California (CAIR-CA), challenges San Jose police officers’ practice of searching for location information collected by automated license plate readers (ALPRs) without first getting a warrant.  

ALPRs are an invasive mass-surveillance technology: high-speed, computer-controlled cameras that automatically capture images of the license plates of every driver that passes by, without any suspicion that the driver has broken the law. 

“A person who regularly drives through an area subject to ALPR surveillance can have their location information captured multiple times per day,” the lawsuit says. “This information can reveal travel patterns and provide an intimate window into a person’s life as they travel from home to work, drop off their children at school, or park at a house of worship, a doctor’s office, or a protest. It could also reveal whether a person crossed state lines to seek health care in California.”

The San Jose Police Department has blanketed the city’s roadways with nearly 500 ALPRs – indiscriminately collecting millions of records per month about people’s movements – and keeps this data for an entire year. Then the department permits its officers and other law enforcement officials from across the state to search this ALPR database to instantly reconstruct people’s locations over time – without first getting a warrant. This is an unchecked police power to scrutinize the movements of San Jose’s residents and visitors as they lawfully travel to work, to the doctor, or to a protest. 

San Jose’s ALPR surveillance program is especially pervasive: Few California law enforcement agencies retain ALPR data for an entire year, and few have deployed nearly 500 cameras.  

The lawsuit, which names the city, its Police Chief Paul Joseph, and its Mayor Matt Mahan as defendants, asks the court to stop the city and its police from searching ALPR data without first obtaining a warrant. Location information reflecting people’s physical movements, even in public spaces, is protected under the Fourth Amendment according to U.S. Supreme Court case law. The California Constitution is even more protective of location privacy, at both Article I, Section 13 (the ban on unreasonable searches) and Article I, Section 1 (the guarantee of privacy). “The SJPD’s widespread collection and searches of ALPR information poses serious threats to communities’ privacy and freedom of movement.”

“This is not just about data or technology — it’s about power, accountability, and our right to move freely without being watched,” said CAIR-San Francisco Bay Area Executive Director Zahra Billoo. “For Muslim communities, and for anyone who has experienced profiling, the knowledge that police can track your every move without cause is chilling. San Jose’s mass surveillance program violates the California Constitution and undermines the privacy rights of every person who drives through the city. We’re going to court to make sure those protections still mean something.” 

“The right to privacy is one of the strongest protections that our immigrant communities have in the face of these acts of violence and terrorism from the federal government,” said SIREN Executive Director Huy Tran. “This case does not raise the question of whether these cameras should be used. What we need to guard against is a surveillance state, particularly when we have seen other cities or counties violate laws that prohibit collaborating with ICE. We can protect the privacy rights of our residents with one simple rule: Access to the data should only happen once approved under a judicial warrant.”  

For the complaint: https://www.eff.org/files/2025/11/18/siren_v._san_jose_-_filed_complaint.pdf

For more about ALPRs: https://sls.eff.org/technologies/automated-license-plate-readers-alprs