California's attorney general is seeking a court order to force Facebook to give up information about how the company handled user data.
Attorney General Xavier Becerra said Facebook has resisted and even ignored California's attempts to get information from the company as part of an investigation launched by his office over whether the company misused data.
He said Facebook has not responded to the subpoena his office has issued.
"We had to file this petition because we weren't getting the responses we believe we were due lawfully," Becerra said at a press conference Wednesday in San Francisco.