Pity John Koskinen, who agreed to take one of the worst jobs in America and is now being punished for it.

In 2013, President Barack Obama asked Koskinen to take over at the Internal Revenue Service amid budgetary chaos, deteriorating morale and a simmering scandal. House Republicans, still angry about that scandal — and about the concept of taxation generally — are now trying to impeach him.

Their case is weak, and the ultimate loser in this sorry spectacle won’t be Koskinen.

Start with the scandal. An inspector general report in 2013 found that IRS employees had been improperly scrutinizing conservative groups seeking tax-exempt status. This was wrong, and blame was duly apportioned. The agency’s boss resigned, a top deputy retired, and the director of the offending unit was placed on leave and declared in contempt of Congress. Half a dozen congressional committees vowed to fumigate every pixel of offending detail. One managed to produce an 8,000-page report. The Justice Department investigated (and found no evidence of criminality).

But you have to get up pretty early in the morning to outfox the House Oversight and Government Reform Committee. Rep. Jason Chaffetz of Utah, the committee’s chairman, has made a professional specialty of berating civil servants. He appears to view Koskinen— who, recall, joined the agency after this scandal — as obstructing further investigation.

The specific allegations Chaffetz has adduced hardly add up to high crimes and misdemeanors. At worst, they portray mild bureaucratic ineptitude. And removing Koskinen from office stands no chance in legislative reality. Nothing’s shaking on Shakedown Street, as they used to say.

Actually impeaching Koskinen — a punishment not invoked against an executive-branch appointee since Ulysses S. Grant occupied the White House — probably isn’t the objective anyway. The point is to embarrass the IRS. And congressional Republicans have already done a fine job of that by slashing the agency’s budget while helping to vastly expand its responsibilities, with predictably frustrating results.

Taxpayers, in other words, are the ones who ultimately suffer when Congress ignores more pressing business in favor of needlessly antagonizing the IRS. They’re also the ones footing the bill for 8,000-page reports and shambolic impeachment proceedings.