Law Professor Jonathan Turley reacted to a New York Times report saying that Special Counsel Bob Mueller is "scrutinizing [President Donald Trump's] tweets and negative statements" about Attorney General Jeff Sessions and former FBI Director Jim Comey.

Trump has criticized both men on Twitter, at one point voicing regret for choosing Sessions for the DOJ post in the wake of his recusal from the probe, in addition to multiple critiques of Comey.

“The recusal of Jeff Sessions was an unforced betrayal of the President of the United States.” JOE DIGENOVA, former U.S. Attorney. — Donald J. Trump (@realDonaldTrump) May 31, 2018

....chief law enforcement officer, and they told me later, ‘oh by the way I’m not going to be able to participate in the most important case in the office, I would be frustrated too...and that’s how I read that - Senator Sessions, why didn’t you tell me before I picked you..... — Donald J. Trump (@realDonaldTrump) May 30, 2018

James Comey better hope that there are no "tapes" of our conversations before he starts leaking to the press! — Donald J. Trump (@realDonaldTrump) May 12, 2017

Turley, who teaches at George Washington University in Foggy Bottom, D.C., said that the prospect of "using Tweets as a criminal mosaic" is "reaching the evidentiary dregs."

He said Trump does not surrender his First Amendment right to free speech simply because he is a world leader.

Turley said he often disagrees with Trump's decision to tweet things, but that his social media presence shows the president "plays poker with the cards facing outward."

He said that if the Times report is true, Mueller would be "undermining his credibility" by relying on tweets for key evidence.

"Reaching for the social media in the form of evidence is a sign of weakness," he said.

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