On learning that former Prince George’s county executive Jack B. Johnson had pleaded guilty to two felonies Tuesday, current County Executive Rushern Baker was at pains to assure his fellow Prince Georgians that they shouldn’t feel dissed.

The news “is by no means reflective of the people of Prince George’s County or employees of its government,” Baker said in a statement.

Well, allow me to respectfully disagree. Prince George’s residents should absolutely feel embarrassed that the most powerful and prominent county official of the past decade is looking at spending most of the next decade in federal prison for corruption.

More importantly, they should let that humiliation prod them to demand a dramatically higher standard of conduct from politicians, bureaucrats and business leaders. The county should stop blaming the media and others for supposedly painting a false picture of its ethics problems, and instead take responsibility for solving them.

U.S. Attorney Rod J. Rosenstein, whose office deserves major kudos for this success in a long, complicated and continuing investigation, said Johnson’s conviction should prompt Prince George’s to build “a culture of integrity” to support honest government.

“We hope that this case . . . will have a beneficial effect for the people of Prince George’s County and the people of Maryland by creating an incentive, creating an opportunity to make positive changes so we won’t need law enforcement actions like this one in the future,” Rosenstein said after the plea.

The rest of the Washington region has a stake in this. Prince George’s is the area’s third-largest jurisdiction and has abundant undeveloped land that gives it tremendous potential for economic growth. But the county will continue to lag behind its more prosperous neighbors if it continues to tolerate public malfeasance.

Let’s look at the record. Prince George’s voters elected Johnson four times to county-wide office – twice as prosecutor, twice as county executive — despite gradually swelling complaints about his administration’s ethics.

In particular, when Johnson won reelection as county executive in 2006, voters already knew about a Washington Post front-page investigation showing he had awarded millions in contracts to friends and political supporters. Two high-ranking county officials had been convicted of felonies in a bribery scheme. Baker himself, who ran against Johnson, campaigned as a reformer who’d clean up county government.

When we in the media raised questions about the county’s “pay to play” business culture, politicians and civic leaders assailed us for being sensationalistic and biased. The county’s problem, we were told, was only one of “perception.”

I know from personal experience. When I was a Post editor before becoming a columnist, I sat through repeated harangues from County Council members and others saying we were being unfair to Prince George’s.

So now, I ask anybody who thinks we exaggerated the problems in Prince George’s to please go read the four federal plea agreements released Tuesday. They provide a detailed portrait of a political and business culture rife with venality.

It isn’t just Johnson’s plea, although that’s a doozy. He admitted he took hundreds of thousands of dollars in bribes and started demanding payoffs from developers soon after becoming county executive. Federal sentencing guidelines suggest he’ll get 11 to 13 years.

The plea agreement by developer Patrick Ricker offers an even broader picture of crookedness at the intersection of politics and business in Prince George’s. He pleaded guilty to conspiracy and tax evasion back in 2009, but the plea was kept secret until now to avoid interfering with the investigation of Johnson and others.

Ricker admitted conspiring with other developers and lobbyists (not yet identified) to bribe politicians in various ways. Those included using phony donors to make contributions to 10 political campaign committees, including in a U.S. Senate race.

In one particularly tantalizing paragraph, Ricker admitted that he and three co-conspirators regularly provided “money, trip expenses, meals, drinks, hotel rooms, airline tickets, rounds of golf, sexual services” and other things of value to state and local officials in “the County’s Executive Branch, Legislative Branch and the Board [of Education], intending to influence them to take and be rewarded for taking a stream of favorable official action.”

As for Johnson, although he told reporters he was sorry for what happened, it seemed clear from other comments that he mainly regretted getting caught. In particular, he suggested that information yet to come would cast his actions in a more favorable light. He also hinted that he pleaded guilty because a trial would mean too much expense and family stress.

That suggests that Johnson is still in denial about his wrongdoing. But Prince George’s needn’t follow his example. The worst political scandal in the county since the 1960s should be the jolt needed so residents fully admit that corruption is a reality, not just a perception, and then definitively end it.

I discuss local issues at 8:51 a.m. Friday on WAMU (88.5 FM).