Trump's latest pardon threat reveals 'what keeps him up at night': expert

President Donald Trump just revealed "what keeps him up at night" after dangling pardons for all of his administration officials, according to one expert.

Last week, the Wall Street Journal reported that Trump has promised to sign mass pardons for administration officials before leaving office. Michael Popok, a lawyer and host of the "Legal AF" podcast, said in a new episode on Sunday that the report shows Trump is clearly aware that he is running a "criminal enterprise" out of the White House and that he fears being prosecuted by a future Democratic Department of Justice more than anything else at this point in his second administration.

"Donald Trump knows he's running a criminal enterprise when the Wall Street Journal just reported that he's joking again about giving everybody in his administration a pardon," Popok said.

"I'm not sure he sleeps, or how he sleeps. I think he sleeps in a coffin at night. But the thing that keeps Donald Trump up at night would be him or others around him being criminally prosecuted, investigated by the future Department of Justice," he added.

Popok added that he would not be surprised if a future DOJ investigation into Trump tested the limits of the Supreme Court's recent presidential immunity decision. He argued that the decision further blurred the line between public and private presidential conduct and that a future DOJ may be willing to test its limits.

"That immunity decision is just waiting to be challenged and tested and to have the Supreme Court either roll it back, nip it, tuck it in, or revisit it," Popok said. "And the only way you can do that is with a prosecution. So I envision ... there will be an investigation prosecution of Donald Trump when he leaves office, with a statute of limitations that's remaining to get a case back to the Supreme Court, depending upon who's up there to see what happens with that immunity decision."