Tucker: Flynn's Guilty Plea Doesn't Prove Collusion

Judge Nap: How Flynn Plea Deal Could Lead to 'Constitutional Crisis'

Harvard Law School professor emeritus Alan Dershowitz believes that Robert Mueller's plea deal with Gen. Michael Flynn may actually be a "show of weakness" in the special counsel's Russia investigation.

On "America's Newsroom," Dershowitz explained that Flynn pleaded guilty to lying to the FBI, and the last thing a prosecutor ever wants to do is to charge a key witness with lying.

"It makes it clear that you can't trust this guy," he said.

He added that Mueller would have preferred to indict Flynn for conspiracy or some other crime directly involving other people, but he apparently lacks the evidence to do so.

"It doesn't show strength when you go after your main witness and call him a liar," Dershowitz said.

As for his assessment that President Trump cannot be charged with obstruction of justice for asking former FBI Director James Comey to end the bureau's investigation into Flynn or for later firing Comey, Dershowitz clarified his comments.

"A president can be charged with obstruction of justice if he goes beyond his Article II constitutional authority," he said. "That authority includes pardoning anybody and firing anybody in the Executive."

He explained if a president told somebody to lie to authorities, paid "hush money" or destroyed evidence - as former President Richard Nixon did in the Watergate scandal - that would constitute an independent basis outside of Article II for obstruction charges.

"Nobody is above the law," Dershowitz said.

Watch more above, and see Judge Andrew Napolitano's analysis of potential obstruction charges.

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