Is Mark Meadows cooperating with Jan. 6 investigators? If so it's 'game over': legal experts

Mark Meadows is rumored to be cooperating with federal investigators looking into Donald Trump's efforts to overturn his 2020 election loss, which legal experts say could be ruinous for the former president.

A source connected to Trump told CNN they've heard rumors that the former White House chief of staff, who's advising Republican lawmakers during the ongoing debt-ceiling negotiation, may be cooperating with federal investigators or possibly is a target of a criminal probe himself, and Newsweek reported that legal expert Ryan Goodman said that would be a major development.

"If he's cooperating, it's game over," tweeted Goodman, a former Defense Department special counsel.

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Meadows spent Jan. 6, 2021, with Trump as the insurrection unfolded and played a key role in the ex-president's attempts to remain in power in spite of his election loss, and he reportedly was in direct communication with the organizers of the "Stop the Steal" protest that preceded the U.S. Capitol riot.

Special counsel Jack Smith reportedly subpoenaed Meadows in February to testify before a special grand jury, but it's unclear whether he has answered questions under oath after a judge rejected Trump's claims of executive privilege over his testimony.

"I'll believe it when I see it," tweeted Harry Litman, a former deputy attorney general, of Meadows' testimony.