Jeffrey E. Thompson, the now-fallen captain of the government-contracting scheme, long had the pleasure of playing the big shot, tooling around town like Lady Bountiful, conspicuously and benevolently shelling out other people’s money. For years, Thompson lived high on the hog courtesy of D.C. and federal government contracts, grazing on chops and loins while some lesser taxpayers were left to get by on pig’s feet and chitterlings.

Thompson was known for extravagantly giving money to politicians and for greedily swallowing the government business that flowed his way. It mattered not that the philanthropy attached to his name was made possible by the public treasury. He was given to calling himself “The Admiral,” and our nation’s capital was his sea.

Now Thompson may be called to pay. And with good reason. In his quest for riches and glory, he has made an unholy mess of things.

D.C. Chartered Health Plan, the company he founded and owned, used to operate the city’s largest contract, worth more than $350 million. But the company was run into the ground. D.C. taxpayers ended up shelling out nearly $50 million last year to settle its bad accounts.

The accounting firm that Thompson founded had boatloads of government clients. After Thompson left and an audit was conducted, the firm acknowleged that some of its employees, their relatives and friends contributed political campaigns — and were reimbursed at Thompson’s direction.

It is there, in the arena of campaign finance, where Thompson contributed to the pollution of the city’s political process.

The Post reported that he is in the final stages of talks with U.S. Attorney Ronald C. Machen Jr. and his prosecutors to strike a plea agreement.

Little wonder it has come to that.

Thompson has been identified by associates as the moneybags behind the surreptitious “shadow campaign,” an off-the-books effort on behalf of Vincent C. Gray (D) that pumped more than $600,000 into the 2010 D.C. mayoral election. If true, Thompson’s actions would represent the worst subversion of an election in the history of D.C. home rule.

The impact of Thompson’s alleged behavior, however, is being felt beyond the sullied results of that election. The dark cloud of that campaign hovers over next month’s Democratic primary for mayor. At least two of the candidates have been drawn into the ongoing federal investigation.

D.C. Council member Jack Evans (Ward 2) has received a federal grand jury subpoena for records related to contributions by Thompson. And D.C. Council member Vincent Orange (At-Large) has met with federal prosecutors and turned over subpoenaed campaign records.

D.C. Council member Muriel Bowser (Ward 4) has refused to say whether her campaign has received a federal subpoena.

Four of Gray’s close friends and top campaign aides — Howard L. Brooks, Thomas W. Gore, Jeanne Clarke Harris and Vernon E. Hawkins — have pleaded guilty to misdeeds associated with the 2010 election. Gray has not been charged with any crime, and he has denied any wrongdoing.

But only a fool or a knave would contend that Machen doesn’t have an eye on Gray. And the drumbeat of federal criminal action will echo throughout this election year.

As the city swings into the general election this fall, former D.C. Council member Michael A. Brown is to go before a federal judge for sentencing. Jeanne Clarke Harris’s March 19 status hearing in federal court is expected to be rescheduled, with sentencing to occur after the April 1 primary. Hawkins is to be sentenced sometime after April 1, too. All three are reported to be cooperating with prosecutors.

Now there is Thompson and the reported plea negotiations. Machen has no choice but to press on, the federal entanglement in the city’s electoral process notwithstanding. This year, the cause of justice marches side by side with the exercise of self-government.

If federal prosecutors have evidence to support the conviction of anyone involved in the subversion of campaign laws, whether it is an architect of illegal campaign spending or corrupt and lying candidates, charges should be brought now — before D.C. voters head to the polls. Just get on with it.

Neither justice nor clean government is served if a primary-election winner ends up indicted or charged with criminal activity after the votes are counted.

Get after them. Get after them now.

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