Conservative radio talker Mark Levin appears to have touched off the investigation into Internal Revenue Service targeting of conservative political groups back in March 2012.

In a letter last year on behalf of the Landmark Legal Foundation, an organization he heads, Levin requested an investigation into what he called “misconduct.”

On Friday, the Internal Revenue Service revealed that it had improperly targeted conservative groups for audits during the 2012 election. During a conference call, Lois Lerner, the IRS’s director of exempt organizations, explained that IRS staffers selected groups that included the words “tea party” or “patriot” in their applications for tax exempt status.

Levin told The Daily Caller Friday afternoon his organization had litigated similar complaints of political audits during the Clinton administration and specifically referenced the Heritage Foundation as one of the tax collector’s targets at the time.

More recently, Levin said, conservative and Tea Party groups approached him complaining of harassment by the IRS, which prompted his organization to petition Treasury Department Inspector General for Tax Administration J. Russell George.

“So what happened here is we were contacted by a number of individuals with Tea Party affiliations and they were telling us what was going on,” he said. “They were sharing the information with us and we concluded the best way to handle this was to go to the Treasury Department — the inspector general’s office because the IRS per se we didn’t think would conduct a thorough investigation of itself.”

After that initial contact, Levin said two agents from Treasury paid his office a visit seeking more information.

“Shortly after they got the letter, two agents from the Treasury Department’s inspector general’s office did interview me fairly thoroughly at our offices at Landmark — wanted all the information we had, which I provided them and I also discussed with them what I considered the law to be and what I considered the violations to be. I gave them our various contacts and then they left and we never heard from them again, which is typical.”

Landmark Legal Foundation’s March 2012 letter to the Treasury Department Inspector General:

The conservative said that in his view this was more than just misconduct by a few IRS employees and had broader constitutional implications.

“It’s pretty straightforward and remarkable what the IRS was trying to do to these groups, including how it violated the Constitution and the First Amendment without any question,” he added. “The partisan political nature was never in doubt.”

Levin said it was his goal to expose and stop this corruption, and he suggested that this activity went higher up than just “low-level IRS employees.” He also called on Congress to investigate, which Republicans Senate Minority Leader Mitch McConnell of Kentucky and Rep. Darrell Issa of California have already vowed to do.

“I’m extremely skeptical that a couple of low-level IRS employees on their own put together these rather extensive questionnaires for Tea Party groups,” Levin said. “But I noticed today that members of Congress said there are going to be hearings and that’s exactly what’s called for — federal hearings with subpoena power putting people under oath.”

Levin also told The Daily Caller he would be willing to testify before any appropriate congressional committee if called upon.

“I’m happy to testify about what we provided to the Treasury Department and what I advised them,” he said. “It’s no great secret. It’s right there in the letter.”

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