Informal Trump adviser calls Barr 'one of the finest lawyers this country has ever produced'

Joe diGenova, an informal adviser to President TrumpDonald John TrumpPapadopoulos on AG's new powers: 'Trump is now on the offense' Pelosi uses Trump to her advantage Mike Pence delivers West Point commencement address MORE, defended Attorney General William BarrWilliam Pelham BarrPapadopoulos on AG's new powers: 'Trump is now on the offense' House Democrats must insist that Robert Mueller testifies publicly Why Mueller may be fighting a public hearing on Capitol Hill MORE during a Thursday appearance on Hill.TV, saying Barr is "one of the finest lawyers this country has ever produced."

The former U.S. attorney for the District of Columbia and staunch Trump backer made the remarks while being interviewed by hosts Buck Sexton and Krystal Ball, who asked if Barr might have lied in his comments about whether a sitting president can be indicted.

"I'm asking if Barr is a liar, is really the question," Ball said, referencing Thursday's press conference with Barr to discuss special counsel Robert MuellerRobert (Bob) Swan MuellerThe Hill's 12:30 Report: Trump orders more troops to Mideast amid Iran tensions Trump: Democrats just want Mueller to testify for a 'do-over' Graham: Mueller investigation a 'political rectal exam' MORE's report.

"Don't you dare suggest that Bill Barr is a liar," diGenova said. "I've known him for 30 years. He's one of the finest lawyers this country has ever produced."

"There's not one shred of evidence that anything he said — either the other day, or now, or today — was a lie," diGenova added. "Don't ever say that in front of me about Bill Barr. You have no evidence that he lied, and you know it."

"What I'm telling you is that what he said today is inconsistent with what's in the report," Ball responded.

"That's not a lie," diGenova shot back.

"OK, fine," Ball said.

"It's not fine. You're on national television calling the attorney general a liar," diGenova said.

"I didn't say that," Ball responded.

"You suggested it very strongly," diGenova said.

Mueller's report suggests that the investigation into whether Trump obstructed justice was influenced in part by the Justice Department's Office of Legal Counsel (OLC), which says a sitting president cannot be indicted.

Barr told reporters during Thursday's news conference that Justice Department officials had asked Mueller “about the OLC opinion and whether or not he was taking the position that he would have found a crime but for the existence of the OLC opinion.”

“He made it very clear, several times, that he was not taking a position — he was not saying but for the OLC opinion he would have found a crime,” Barr said.

Congressional Democrats have said they want Mueller to testify on Capitol Hill to answer questions about his report.

— Julia Manchester