John Koskinen. AP

WASHINGTON — Nearly one year after Republicans attempted to impeach IRS Commissioner John Koskinen, the official whom conservatives accused of breaching the public trust is still the US government's chief tax collector.

But Koskinen's ability to elude the House Freedom Caucus' desire to remove him from office has left conservatives feeling embittered, and one theorizes that it could be because the IRS is auditing President Donald Trump's tax returns and Trump could be worried about what information Koskinen has on him.

Koskinen's term comes to end on November 12. And while conservatives are glad he is on his way out, they feel a sense of disappointment in their inability to punish the man they say obstructed justice and stonewalled lawmakers.

"I'm extremely disappointed," Rep. Louie Gohmert of Texas told Business Insider. "I think he basically thumbed his nose at all of Congress and we haven't done anything about it, and I think it hurts our credibility."

House Republicans have long accused Koskinen of lying to lawmakers about the IRS' targeting of conservative groups at the height of the tea party's manifestation during the Obama administration. Conservatives charge that Koskinen destroyed documents relating to the targeting, lied about it, and thus should have been impeached.

Rep. Jim Jordan, the Ohio Republican who spearheaded the effort to impeach Koskinen while serving as chairman of the Freedom Caucus, said "we should have ousted him long ago," adding he was glad Koskinen’s term was wrapping up next month.

Rep. Dave Brat of Virginia told Business Insider that the rule of law never applied to Koskinen, even into the Trump administration.

"The IRS was shown to be targeting groups — tea-party groups in my own district — it was proven and nothing happens to big elites," Brat said. "Because they know where bodies are buried on our side and on the other side and, unfortunately, the rule of law is not kicking in."

Brat also floated the idea that Trump did not immediately fire Koskinen upon becoming president because of an ongoing audit of his personal finances.

"I'm speculating on that, but what's one of the key issues with Trump? Tax returns, right?" Brat said. "So it makes you suspicious that it's so bad."

"It's curious when someone has broken the law and the law doesn't kick in — that's a big hint," Brat added. "So I hope that's not the case — I don't know it's the case — but if you just look at the logic and why you're doing the story, something's wrong. Something's very wrong."

Rep. Thomas Massie, a Kentucky Republican, shrugged off Brat's theory, however, saying the Trump administration already had difficulty filling other vacant government positions and perhaps didn't want to create additional openings.

"Probably you don't plow up ground if you can't plant it," Massie said.

A representative for the IRS declined to comment on Brat's theory. The White House did not respond to a request for comment.

At the end of 2016, former Rep. John Fleming of Louisiana pushed for a privileged resolution to force a vote on Koskinen's impeachment. Ultimately, the plan was tabled and safely sent back to the Judiciary Committee.

On Wednesday, The Washington Post reported that a new report from the inspector general suggested liberal groups may have been targeted by the IRS during the Obama administration as well.

Regardless of the circumstances of Koskinen's exit, though, conservatives are breathing a sigh of relief that their archnemesis at the IRS is on his way out.