Lawyers for Rep. Eric Swalwell (D-Calif.) issued a cease-and-desist letter on Monday demanding that FBI Director Kash Patel halt any effort to release records tied to a decade-old FBI investigation involving the California Democrat and a suspected Chinese operative—an inquiry that ultimately led to no criminal charges.

In the March 30 letter, attorneys Sean Hecker and Norm Eisen argue that making the files public would violate federal law as well as long-standing U.S. Department of Justice policies. They requested a response within three days confirming compliance and warned that legal action would follow any attempt to proceed.

“The Congressman has never been accused of wrongdoing in that matter and your attempt to release the file is a transparent attempt to smear him and undermine his campaign for Governor of California,” the letter reads. “Your actions threaten to expose you, others at the FBI, and the FBI itself to significant legal liability. Indeed, disclosure of the investigative file would violate federal law in several respects.”

Eisen and Hecker also said that releasing the files would be a violation the First Amendment.

“By all accounts, your effort to release investigatory files concerning Congressman Swalwell—an outspoken critic of both you and the President—constitutes just such an attempt to punish or suppress disfavored expression,” they wrote.

The Washington Post reported on March 28, based on anonymous sources, that Patel had instructed agents to review and redact materials from the investigation in preparation for possible release. Such a move would be highly unusual, as the Justice Department rarely discloses records from investigations that do not result in charges, according to the news outlet.

The Epoch Times has reached out to the FBI for comment.

The bureau disputed the reporting by the Washington Post and told the outlet that it prepares documents for various purposes.

The investigation centered on Swalwell’s past interactions with Christine Fang, a suspected Chinese intelligence operative who built connections with U.S. political figures. Fang reportedly engaged with Swalwell’s campaign during his first congressional run in 2012 and assisted with fundraising in 2014.

Federal authorities briefed Swalwell and Congress about their concerns in 2015. Swalwell has said he cut off all contact at that point. He was never accused of misconduct, and a House Ethics Committee review opened in 2021 concluded in 2023 without any findings of wrongdoing.

Swalwell, now a candidate for governor of California, has been a prominent critic of President Donald Trump and served as a House manager during Trump’s second impeachment. He has also clashed publicly with Patel, who listed Swalwell among perceived political adversaries in his 2023 book, “Government Gangsters.”

The Associated Press contributed to this report.