A U.S. House hearing on missing emails at the Internal Revenue Service on the targeting of conservative groups turned into a bare-knuckled verbal political brawl, as Republicans accused the IRS chief of misleading Congress and Democrats mocked the GOP for spinning sinister conspiracy theories.

"I don't think an apology is owed," said IRS Commissioner John Koskinen, as he stood by the IRS effort to turn over material to Congress.

"Not a single email has been lost since the start of this investigation," said Koskinen, who was repeatedly lambasted by Republican lawmakers, like this exchange with Rep. Paul Ryan (R-WI), who bluntly said he didn'.

"Nobody believes you," Ryan told Koskinen, which drew an audible protest from the top Democrat on the committee.

Republicans wasted little time putting this exchange on YouTube.

During the hearing in the Ways and Means Committee, Koskinen admitted that he found out earlier this year about the possibility that Lerner's emails could not be recovered, but waited to inform the Congress.

"You failed to explain the timeline of those events," said Rep. Dave Camp (R-MI), who accused Koskinen of withholding information from lawmakers.

"Were you purposely not telling us?" asked Camp.

Koskinen rejected assertions of a coverup, as he also rejected the idea of appointing a special prosecutor to review how the IRS Tea Party targeting matter was dealt with by the tax agency.

"I think the appointment of a special prosector after the six investigations ongoing and the IG investigation into this matter (Lerner's hard drive) would be a monumental waste of taxpayer funds," said Koskinen.

"So, is that a yes or a no?" asked Camp.

"It's a no," Koskinen firmly replied.

As for Lerner's hard drive, GOP lawmakers gasped when Koskinen said it had been recycled and destroyed after the IRS criminal forensic unit was unable to retrieve information from it in the summer of 2011.

Democrats meanwhile chastised the GOP for the aggressive nature of the hearing and for selective outrage, saying nothing shows that Lerner was trying to destroy emails or coverup anything.

"Her computer crashed more than two weeks before she was notified about inappropriate actions that were occuring in Cincinnati," said Rep. Joe Courtney (D-NY), who lopped critics of the IRS into the same boat as those who don't believe that President Obama was born a U.S. citizen.