Ty Cobb, former White House attorney to Donald Trump, delivered a stark warning about his former employer on Tuesday night.

“I think you have to take Trump seriously because he poses the gravest threat to American democracy that we’ve ever seen,” Cobb said on CNN.

Cobb, who led the White House response to the Russia investigation in 2017-2018, dismissed Trump’s legal argument that he has “absolute immunity” from prosecution for acts committed while president. Cobb said Trump is just using the case, which is currently before the D.C. Circuit Court of Appeals, as a delay tactic.

He called the notion of such blanket immunity “very scary” as it would mean American presidents have virtually no accountability apart from impeachment.

“I think the lack of accountability which he desires, which Putin has, which the Ayatollah has, which Xi has... he may want an America like that,” Cobb said, referring to the leaders of Russia, Iran and China.

However, he said the nation’s founders wanted America’s leaders to be accountable, and predicted Trump would lose the case, with a decision coming “fast and forcefully.”

See most of his conversation with CNN’s Erin Burnett below: