It is no secret that Wisconsin Governor Scott Walker would like very much to have his name added to the long shortlist of 2016 Republican presidential contenders. But the nation’s most militant anti-labor politician has suddenly been thrust into the center of a scandal that is likely to dim his national prospects, and that could yet cost him his state post.

Even after major setbacks for Walker’s Republicans in Wisconsin—where Barack Obama easily beat Mitt Romney and progressive Democrat secured the state’s open US Senate seat—the governor was jetting off to California last week to make high-profile appearances at the Ronald Reagan Presidential Library in Simi Valley, California. And Walker—who came to national prominence in Febreuary 2011 after turning conservative talking pointrs into an anti-labor agenda so militant that it sparked mass protests and a recall campaign—was again performing conservative due diligence last week: refusing to develop a state-run health insurance exchange as part of an ongoing protest against the Affordable Care Act.

But while Walker was piling up presidential points for 2016, a scandal that has plagued him since his election to the governorship in 2010 was taking a dramatic and destructive turn.

At the sentencing hearing for a top Walker aide convicted of felony misconduct in office, the chief prosecutor revealed that when Walker was seeking the governorship in 2010 he was part of an ongoing scheme to use county employees and resources to aid his campaign.

Milwaukee County Assistant District Attorney Bruce Landgraf used the sentencing hearing to detail how Walker and his county and campaign aides “routinely commingled political and official county business”—as the Milwaukee Journal Sentinel described the way in which “campaign, county work intertwined under Walker.”

Wisconsin media exploded late Monday with reports from inside the courtroom, where Walker aide Kelly Rindfleisch was sentenced to six months in jail and three years of probation. The sentence did not come as a surprise after a long John Doe inquiry that has seen numerous Walker aides and associates charged with felonies and misdemeanors. But the direct linking of Walker to potentially illegal activities in the county executive office was news.

According to one report:

Prosecutors today said Scott Walker had regular meetings with his Milwaukee County staffers and his 2010 guv campaign to ensure there was “good coordination” between the two.

Milwaukee County prosecutors made the disclosure during the sentencing of Kelly Rindfleisch, a former Walker county aide who reached a plea deal to settle charges against her stemming from the long-running John Doe probe.

Assistant District Attorney Bruce Landgraf said the group that met regularly included people from Walker’s campaign such as campaign manager Keith Gilkes and spokeswoman Jill Bader along with county employees such as chief of staff Tom Nardelli, spokeswoman Fran McLaughlin, administration director Cindy Archer and Rindfleisch, according to email correspondence obtained by investigators.

The revelations caused consternation in the courtroom, Rindfleisch’s lawyer, Frank Gimbel, was nonplussed. After Landgraf’s sixty-five-minute detailing of wrongdoing by Walker and his aides, Gimbel objected that his client was “the only one of those mentioned in the power point who’s facing jail time.”

Described as “raising both hands in exasperation,” Gimbel reportedly grumbled about the irony that “Scott Walker has not been accused of any wrongdoing.”

Landgraf did not say during his powerpoint presentation in the courtroom whether Walker or others would be charged as part of the exteneded John Doe inquiry into official and political corruption. After the sentencing, he refused to answer questions—maintaining the rigid professionalism of that has characterized the John Doe inquiry over the past two years.

But Monday’s presentation, the first to explicitly link Walker to courthouse wrongdoing, shook the state, where Walker survived a recall election only after repeatedly declaring that he was not a target of the John Doe investigation.

Democratic Party of Wisconsin spokesman Graeme Zielinski says: “It’s clear now that he presided over a criminal culture where county government in Milwaukee became an adjunct of his campaign. The citizens of Wisconsin should be afraid that this criminal culture has been imported to Madison.”

As Walker tries to gin up a presidential campaign, those questions will extend beyond Wisconsin.

That’s not good news for Scott Walker. But it should put a spring in the step of every other Republican who is thinking of running for president.

If Walker’s out of the picture, is it time for Palin 2016? Check out Ben Adler on the conservative pundits pushing for Mama Grizzly’s presidential bid