A former assistant Watergate prosecutor said Wednesday that his official legal opinion on conservative author and conspiracy theorist Jerome Corsi is “liar, liar pants on fire.”

Corsi appeared on Ari Melber's MSNBC show on Wednesday and was grilled about his involvement with special counsel Robert MuellerRobert (Bob) Swan MuellerKamala Harris says her Justice Dept would have 'no choice' but to prosecute Trump for obstruction Kamala Harris says her Justice Dept would have 'no choice' but to prosecute Trump for obstruction Dem committees win new powers to investigate Trump MORE’s probe into Russia’s 2016 election interference and possible collusion between the Trump campaign and Moscow.

ADVERTISEMENT

Shortly after Corsi’s interview, former special prosecutor Nick Akerman said “this guy is not telling the truth.”

“Let me start off with my legal opinion,” Ackerman said on MSNBC. “Liar, liar, pants on fire.”

Draft court documents show Corsi initially told investigators that he declined a request from an individual, whom Corsi identified as Roger Stone, to get in touch with WikiLeaks about "pending ... emails."

Corsi later replied to Stone, “Word is friend in embassy plans 2 more dumps. One shortly after I’m back. 2nd in Oct. Impact planned to be very damaging," appearing to refer to WikiLeaks founder Julian Assange and the dump of hacked Democratic emails weeks before the 2016 presidential election.

Stone and Corsi have both denied being in contact with Assange.

The "real killer here that really puts the lie to him," Akerman said, is that Corsi later deleted those emails between Jan. 13, 2017, and March 1, 2017.

“That time period is really significant because that’s when the congressional committee, the Senate committee, was bringing in Roger StoneRoger Jason StoneHouse panel subpoenas Flynn, Gates House panel subpoenas Flynn, Gates Court orders release of sealed documents in mysterious Mueller grand jury case MORE and was starting to ask questions about this,” Akerman said. “This is not something that somebody forgets.”

Mueller is probing both Stone and Corsi as part of the investigation into Russia’s election interference.

Corsi told Melber on Wednesday that he “absolutely” intended to help Trump’s campaign by trying to get 2016 Democratic presidential nominee Hillary ClintonHillary Diane Rodham ClintonDemocrats bristle as Hicks appears for daylong Capitol Hill testimony Democrats bristle as Hicks appears for daylong Capitol Hill testimony Trump: 'So sad' Democrats are putting Hope Hicks 'through hell' MORE’s stolen emails from WikiLeaks.

“Everybody in the world who was in news or political operations after July 22nd 2016 when Assange dumped all these emails on [then-Democratic National Committee Chairwoman] Debbie Wasserman-Schultz and said he had more, everyone wanted to know what they were,” Corsi explained.