Constitutional scholar Jonathan Turley urged caution to those calling for the impeachment of President Donald Trump, saying actual evidence of a crime remains to be seen.  

Turley weighed in on the report that FBI Director James Comey wrote a memo in which he accused Trump of asking him to shut down the investigation into Michael Flynn.

"The criminal code demands more than what Comey reportedly describes in his memo," Turley wrote in op-ed Wednesday.

The most Flynn was accused of was a violation of the Foreign Agents Registration Act (FARA), Turley said on "Happening Now."

"The suggestion that you would impeach a president for obstruction based on a FARA violation is a little silly," he remarked.

He added that obstruction of justice usually involves a judicial or congressional proceeding, and pointed out there was none present when the supposed conversation between Comey and Trump took place.

However, if Trump had threatened to fire Comey unless he ended the Flynn investigation, that would rise to the level of possible impeachment, Turley told host Jon Scott.

"Even if something is not actionable as a criminal charge it can be a valid basis for impeachment."

Scott noted that the president's supposed comments to the FBI director sounded more like a friend advocating for "soft treatment" of another, not necessarily a criminal act.  

"It certainly doesn't sound like obstruction," Turley agreed.

"I don't want to gild the lily here. This is certainly something that is worthy of investigation. If the president said this, and he said he didn't, it would have been a terrible mistake."

Watch the full discussion above.

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