New court documents filed Wednesday give the first look into the state of California's 18-month-long investigation into Facebook's privacy dealings.

In those documents, California State Attorney General Xavier Becerra says Facebook has been "dragging its feet" by failing to comply with subpoenas for more information related to the state's ongoing privacy investigation into the company and Cambridge Analytica.

It represents the first time the state has acknowledged the probe into Facebook, which was first opened in 2018. Investigators don't typically disclose active probes, "unless there's a legal action that makes it public," Becerra said at a press conference announcing the filing.

"This is one of those times," Becerra said. "If Facebook had complied with our legitimate investigative requests, we would not be making these announcements today, but our work must move forward."

In a statement to CNBC, Will Castleberry, Facebook's VP of state and local policy said the company has "cooperated extensively" with the investigation, but did not address the state AG's filing that said it hasn't complied with subpoenas.

"We have cooperated extensively with the State of California's investigation," Castleberry said in the statement. "To date we have provided thousands of pages of written responses and hundreds of thousands of documents."