House Oversight and Government Reform Committee Chairman Darrell Issa (R-Calif.) angrily blasted IRS Commissioner John Koskinen Monday night for dodging questions about when he learned about Lois Lerner’s lost emails, and why it took so long to tell Congress.

Issa opened the hearing by saying Koskinen promised he would deliver all of Lerner’s emails back in March, and said Koskinen has so far failed to deliver on that promise. After the end of a tense back-and-forth between the two, Issa essentially dismissed Koskinen as untrustworthy.

“My time has expired and I’ve lost my patience with you,” Issa said.

Just like the Ways & Means Committee did last week, Issa noted that Koskinen was made aware of the possibility of problems gathering Lerner’s emails back in February, but didn’t tell Congress they were lost until a 10 days ago. Issa argued to Koskinen that if the IRS were backing up all emails as required, none of the emails would have been lost.

“All emails are not official records under any official records act,” Koskinen replied.

That answer seems to go against IRS rules, which say all emails must be printed out. Current U.S. law also appears to require the IRS to back up all of its systems.

Koskinen also said it would have cost another $30 million to pay for new systems to back up files properly. But Issa dismissed that by saying the IRS has a $1.8 billion IT budget.

“On $1.8 billion, isn’t the retention of key documents that the American people need to count on, like whether or not they’re being honestly treated by your employees… isn’t that in fact a priority that should’ve allowed for full retention?” Issa asked.

To that, Koskinen said, “If we had the right resources, there’d be a lot of priorities we’d have.” But Issa again dismissed that answer as one that implies that maybe American taxpayers shouldn’t have to file taxes at all, since the IRS is apparently not backing up any information.

Issa lost his patience soon after, when he again pressed Koskinen on why he promised all of Lerner’s emails, when he knew they might not all be available.

“I did not say I would provide you emails that disappeared,” Koskinen said. “If you have a magical way for me to do that, I’d be happy to know about it.”

Just as they did last week, Democrats apologized to Koskinen for the harsh questioning from Republicans.

“This is about theater,” said Rep. Gerry Connolly (D-Va.). “Fair play, presumption of innocence, civility, respect for an honored public servant who’s serving this country yet again, are out the window.”

Del. Eleanor Holmes Norton (D-DC) apologized for his treatment before the committee. “I believe you deserve one,” Norton said.

Republicans have been looking for all of Lerner’s emails for evidence that she and others purposefully targeted conservative groups seeking tax-exempt status. Issa started the hearing by saying the IRS appears to be covering up its tracks.

“Transparency clearly did not compel the IRS to tell the truth about Lois Lerner’s lost emails,” Issa said. “You worked to cover up the fact that there were missing emails, and came forward to fess up only on Friday afternoon, after you had effectively been caught red-handed.”

“You gave your word, sir, and we are just a little questioning what your word is worth if in fact you cannot enlighten us about what you know,” he said.

Issa also compared the IRS targeting scandal and the resulting coverup to Watergate, and said historians will have to study the issue without the aid of direct testimony from Lerner. Lerner refused to testify before Congress earlier this year.

“This event in history, like Watergate, like Teapot Dome and like many other historic events, will be studied by future generations without the benefit of many of the thoughts and actions of Lois Lerner and others at the IRS as a result of your organization’s failure,” he said.

Koskinen infuriated Republicans last week by refusing to apologize for taking more than three months to tell Congress that some of Lois Lerner’s emails were missing. At a Ways & Means Committee hearing on Friday, Koskinen said the IRS wanted more time to figure out the problem, but Republicans noted that the IRS ultimately decided to bury the news in a long memo less than two weeks ago.

He offered largely the same testimony Monday night, and reiterated that Lerner and other officials tried but failed to recover all emails related Lerner’s account.

Last week, Koskinen’s description of what happened led House Budget Committee Chairman Paul Ryan (R-Wis.) to say he doesn’t believe Koskinen at all. “I don’t believe it,” he said. “That’s your problem, nobody believes you.”

TheBlaze Furnace Editor Pete Kasperowicz joined Editor in Chief Scott Baker on today’s BlazeCast: