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Top congressional Republicans made their case Tuesday to impeach IRS Commissioner John Koskinen, testifying before the House Judiciary Committee that he intentionally ignored and “lied” to Congress about the agency’s 2010 targeting scandal.

“We were lied to in Congress. We were misled in Congress,” said Rep. Jason Chaffetz, chairman of the House Commitee on Oversight and Government Reform, which is seeking Koskinen’s removal.

The commissioner, in a written statement, called the charges "unfounded" but did not personally testify before the committee.

The unusual hearing Tuesday instead featured Republican lawmakers outlining to their colleagues why they believe impeachment should be pursued. Chaffetz has 73 co-sponsors on his impeachment resolution -- but support from other Republicans has been tepid and Democrats are flatly opposed.

The Utah Republican argued Tuesday that impeachment appears the remedy of last resort, after years of investigations and findings by his panel yielded few results.

He also testified that Koskinen’s conduct before Congress is impeachable. Chaffetz specifically has accused Koskinen of failing to provide congressional investigators with subpoenaed evidence, not testifying truthfully about the destruction of emails and taking three months to reveal to Congress that emails considered important to the probe were missing. 

“The facts before us on the impeachment go solely to what Mr. Koskinen did and didn’t do when he was under subpoena,” Chaffetz told the Republican-led Judiciary committee, which handles the chamber’s impeachment requests. “There was a lot of gross negligence, things he should have done, could have done.”

In 2010, the IRS began subjecting conservative groups seeking tax-exempt status to unusually tough scrutiny, prompting GOP lawmakers to launch congressional investigations, cut the agency's budget and trim its staffing.

In May 2013, the agency acknowledged the targeting. Koskinen was nominated by President Obama later that year and began running the agency in December 2013.

But in 2014, the IRS disclosed it had lost emails to and from Lois Lerner, who headed the agency division that processes applications for tax-exempt status. Chaffetz alleges that 422 IRS backup computer tapes containing up to 24,000 of Lerner's emails were destroyed while Koskinen was in charge.

Florida GOP Rep. Ron DeSantis also argued that while Koskinen said he made every effort to find backup computer tapes for Lerner’s lost emails, an IRS inspector general simply drove to a government warehouse in West Virginia to recover at least some of them.

“This is a sorry train of false statements,” DeSantis told the committee. “Americans will never get the truth.”

House Speaker Paul Ryan, R-Wis., has yet to embrace the impeachment push, with spokesman Brendan Buck saying Ryan has deferred to committee leaders.

Many Republicans would rather not launch a campaign-season impeachment effort with little chance of success.

The hearing Tuesday started with partisan wrangling.

Committee Chairman Rep. Bob Goodlatte refused to allow Koskinen’s written testimony to become part of the official record, arguing it was not subject to questions by committee members.

“This is Lois Lerner all over again,” said committee member and California GOP Rep. Darrell Issa, referring to Lerner invoking the Fifth Amendment on the scandal so she did not have to testify before Congress.

Michigan Rep. John Conyers, the top Democrat on the committee, acknowledged the evidence presented by Chaffetz and others suggested mistakes by Koskinen and other IRS commissioners but questioned whether Koskinen’s reached the level of “gross negligence” and were bad enough for him to be impeached.

“Is this being a little heavy handed?” he asked.

To impeach a federal official, a majority of the House must vote to proceed. It then takes a two-thirds majority vote of the Senate to actually remove the official from office.

The Senate's minority Democrats could easily block the effort, leaving many to believe that Majority Leader Mitch McConnell, R-Ky., won't even try. McConnell spokesman Donald Stewart declined to comment on the subject last week.

In his statement Monday, Koskinen said he delayed telling Congress about missing emails until his agency could assess how much data had been lost. He also said he assured Congress that all emails had been preserved -- which turned out to be untrue -- only because he wasn't aware at the time that data containing the emails had been destroyed.

"The allegations that I somehow attempted to deceive Congress are unfounded," he said.

Last July, a report by IRS Inspector General Russell George concluded that the data were destroyed by mistake, not in any agency effort to withhold information from Congress.

The Justice Department ended a two-year investigation of the controversy last year, saying no IRS official would face criminal charges and that it had uncovered no evidence that agency officials acted out of political bias against conservative groups.

Koskinen's term as IRS commissioner expires in November 2017, 10 months into the next president's term.

“The reality is there are 90,000 good, hard-working people there,” Chaffetz also said. “But they are being mismanaged and led by somebody who is lying to Congress.”

The Associated Press contributed to this report.