Lanny Davis, a longtime Clinton family ally, revealed he was interviewed by the Justice Department inspector general for its investigation into the FBI's handling of the Hillary Clinton emails probe.

Moreover, Davis, who served as a special counsel to former President Bill Clinton, predicts Inspector General Michael Horowitz will come down "very hard" on Comey in its final assessment.

During an interview with Bill O'Reilly on the former Fox News host's website, Davis explained why he thought Comey should have been fired by former President Barack Obama and former Attorney General Loretta Lynch.

"I was interviewed by the inspector general. I only told one reporter that and it was never written," he said. "So this is my first to say that I was interviewed after my making a phone call researching my book that I considered James Comey to have acted unethically and that he should have been fired by Barack Obama and Loretta Lynch because he violated Justice Department policies by holding a press conference and expressing his opinion publicly on the evidence."

[Related: James Comey teases secret Loretta Lynch bombshell, says she was 'tortured' by Hillary Clinton email investigation]

Davis appeared to be referring to Comey's summer 2016 press conference announcing that no charges should be brought against Hillary Clinton for her use of an unauthorized email server during her time as secretary of state.

Davis also condemned Comey, who was fired by President Trump last spring, for writing a letter to Congress saying he was reopening the investigation less than two weeks before the 2016 presidential election.

"That's a firing offense. His decision to write a letter 11 days before the election, whether it hurt Clinton or hurt Trump, was not consistent with 50 years of Justice Department policy to do nothing that might impact presidential elections," Davis argued.

A couple days before the election, Comey revealed the case had been closed again and that the FBI maintained its prior position.

Davis said he gave the IG documents in conjunction with an interview and predicted future trouble for Comey, who is coming out with a book next week.

"Documents that were never seen before, but posted two months after the election that showed that the whole email investigation was botched," Davis said. "So I think that's where the inspector general will come down on Comey very hard as well as on [former FBI Deputy Director Andrew] McCabe."

The IG's wide-ranging report has yet to be released, though it could be unveiled soon. The watchdog began looking into allegations of misconduct in January 2017.