(CNN) House Intelligence Chairman Adam Schiff on Tuesday sent a criminal referral to the Justice Department for Blackwater founder Erik Prince , charging that Prince "willingly misled" the intelligence panel when he testified in 2017.

Prince's testimony has come under scrutiny after the release of special counsel Robert Mueller's report, which raised questions about Prince's meeting with a high-ranking Russian official during the Trump transition.

In a letter to Attorney General William Barr referring Prince, Schiff cited six instances from Prince's testimony that he said were contradicted by the Mueller report.

"The report reveals that Mr. Prince's testimony before the committee was replete with manifest and substantial falsehoods that materially impaired the committee's investigation," Schiff wrote in the letter

Congress has the ability to send criminal referrals to the Justice Department, which is in effect a request that the Justice Department investigate whether crimes were committed. Congressional Republicans have also submitted referrals to the Justice Department related to the various congressional Russia investigations, including for ex-British intelligence agent Christopher Steele and former Trump attorney Michael Cohen. Mueller's team also accused Roger Stone of lying to the House Intelligence Committee in its indictment of Stone. Stone has pleaded not guilty.

Matthew Schwartz, a lawyer for Prince, said in a statement there was "no new evidence here."

"Erik Prince's House testimony has been public for months, including at all times that Mr. Prince met with the special counsel's office," Schwartz said. "Mr. Prince cooperated completely with the special counsel's investigation, as its report demonstrates. There is nothing new here for the Department of Justice to consider, nor is there any reason to question the special counsel's decision to credit Mr. Prince and rely on him in drafting its report."

Prince testified before the House Intelligence Committee in 2017 behind closed doors, and a transcript was later released publicly . Schiff said his criminal referral is tied to Prince's statements on his meeting in the Seychelles Islands with Kirill Dmitriev, the chief executive officer of Russia's sovereign wealth fund.

Prince told the committee that the January 2017 meeting was a chance encounter in a bar following a meeting with George Nader , an emissary for the United Arab Emirates. He also said he was not representing Trump in any way.

But the Mueller report poked several holes in that story.

Mueller wrote that the meeting with Dmitriev was established prior to Prince's trip, and Prince told Dmitriev he would relay information back to Trump's then-chief strategist Steve Bannon. Prince and Dmitriev also met twice, first in Nader's villa and then in a restaurant, according to the Mueller report.

Schiff said that he chose to send the referral to the Justice Department because "the special counsel's report makes it so clear that there are deep reasons to believe his testimony before the committee was false and misleading and deliberately so.

"And so we felt that warranted the extraordinary step of making a criminal referral," he said.

But Schiff also acknowledged that a criminal case could be hard to make because of the circumstances that Prince testified to Mueller.

"You can't lie to Congress ... but if the evidence that his testimony is false was given to the Justice Department by Prince under the condition it not be used against him, then being able to prove the case may be problematic," Schiff said at a Washington Post Live event . "But that's something the Justice Department will need to carefully scrutinize."

Schiff declined to say whether he is considering sending any other criminal referrals for other witnesses who have testified before his committee, such as Trump's son Donald Trump Jr. and son-in-law Jared Kushner.

This story has been updated.