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Law enforcement agencies across Southern California violated state law more than 100 times last month by sharing information from automated license plate readers with federal agents, records show.

The Los Angeles Police Department and sheriff’s departments in San Diego and Orange counties searched license plate readings on behalf of Immigration and Customs Enforcement and Customs and Border Protection, according to a database of queries obtained by anti-surveillance group Oakland Privacy and provided to CalMatters.

Under a 10-year-old California measure, known as Senate Bill 34, state law enforcement agencies are barred from sharing license plate reader data with out-of-state public agencies or federal entities. The law has been routinely violated; civil liberties groups in 2023 found that 71 California law enforcement agencies had broken it. Later that year, Attorney General Rob Bonta issued an advisory providing police with specific guidance on how to comply with the law.