California Attorney General Xavier Becerra is taking Facebook to court to force it to turn over evidence for a newly revealed state investigation into the social network giant's privacy practices.

The big picture: The challenge adds one more layer of trouble for the beleaguered company, which already faces a slew of antitrust investigations and privacy probes in the U.S. and the EU.

Driving the news: In a filing with the San Francisco County Superior Court, Becerra says Facebook has failed to comply with subpoenas for documents and emails. The company's responses have been "patently inadequate," Becerra said at a Wednesday press conference.

"Among other things, we’ve asked for information regarding the effect of the company’s various privacy settings on third parties’ access to data, including which apps Facebook granted access to user data despite users restricting access to their information," Becerra said.

Details: The attorney general’s subpoena seeks communications among executives on:

Any consideration of the need to audit developers’ access to user data.

Third parties who received expanded access to the data.

The relationship between ad spending and access to data.

What they're saying:

Facebook "has not been fully responsive," Becerra said. "They have also failed to provide, or even search for, responsive documents among the emails of the company’s chief executive Mark Zuckerberg and its chief operating officer Sheryl Sandberg."

“We have cooperated extensively with the State of California’s investigation," Will Castleberry, Facebook vice president of state and local policy, said in a statement. "To date, we have provided thousands of pages of written responses and hundreds of thousands of documents.”

Read the petition: