WASHINGTON — GOP Gov. Bruce Rauner and Democratic Attorney General Lisa Madigan were both inside the Supreme Court on Monday for Janus v AFSCME Council 31 oral arguments — a big Illinois case and a high point of the Rauner crusade to eradicate public sector unions.

After the court session, both Rauner and Madigan talked to reporters on the steps of the Supreme Court about what could be a landmark ruling.

Rauner, Madigan: They are on opposing sides of this Illinois case that could destroy public sector unions by allowing workers to stop paying fees to cover the costs of a union representing them — even if they do not belong to the union.

That the public sector unions tilt Democratic and are active in politics is part of the usually unspoken — but obvious — part of this story.

A decision from the justices is not due until June, but the case has real-time political ramifications for Rauner in his upcoming March 20 Republican primary and the November general election as he seeks a second term.

Mark Janus works at the State of Illinois Department of Healthcare and Family Services as a child support specialist. AFSCME Council 31 represents State of Illinois workers.

There is a significant legal distinction between “fair share fees” at issue in this case, and dues a union member pays, though Rauner on the Supreme Court steps Monday said he sees little difference.

Rauner, who has made diluting the power of public sector unions a centerpiece of his tenure, said there is a “fundamental conflict of interest when a government (employed) union boss can give campaign contributions . . . and then after they are elected, negotiate with them on a new union contracts.

“If that happened in the private sector, someone would go to jail. In government it is standard,” Rauner said.

Rauner was careful to make a distinction between public sector unions and private sector labor organizations, stating, “. . . this has nothing to do with trade unions.”

When I asked him why he kept using the word dues and not fees, Rauner replied, “any types of dues, any types of fees is violation of free speech.”

“. . . By its nature, everything a government related union does is political.”

The union-friendly Madigan, a few minutes later said, “This is a case where there are a small group of very well-funded right-wing extremists that want to eliminate unions throughout this country.”

Attorney General Lisa Madigan speaks at a union rally outside the Supreme Court Monday. | Lynn Sweet/Sun-Times

At one time Rauner was allied with some of the groups Madigan was referencing — some of the organizations financing the Janus v AFSCME lawsuit.

No more.

One of those groups is the Liberty Justice Center in Chicago, associated with the Illinois Policy Institute. Its funders included a foundation controlled by Lake Forest conservative mega donor Richard Uihlein.

Uihlein is now a prime funder behind Rauner GOP primary challenger Rep. Jeanne Ives, R-Wheaton.

Liberty Justice Center Vice President Diana Rickert — who for a short time was on Rauner’s communications team — on Monday sent me an email flagging a letter the center sent to Rauner accusing him of inflating his role in the Janus case.

“You have made Janus a centerpiece of your re-election campaign,” the letter said, in part by “touting this case in campaign related events and interviews.”

Rauner is the father of the case: In February, 2015, he issued an executive order to state agencies to stop enforcing the fair share fees. He filed a lawsuit asserting the fee collection was unconstitutional.

A lower court judge said Rauner did not have standing. That’s why Janus — a state worker — was swapped in and became the face of the case. The Janus appeals were paid for by a group of anti-union organizations, with some now anti-Rauner.

RAUNER AT THE TRUMP WHITE HOUSE

Ives is challenging Rauner from the right. Rauner, who has distanced himself from President Donald Trump, went to the National Governors Association Ball hosted by Trump at the White House on Sunday.

After I asked, Rauner said it was the first time they met. Trump and Rauner did not talk “on any extensive basis. It was more of a social opportunity,” Rauner said.

Rauner spent more time with Vice President Mike Pence and his chief of staff Nick Ayers, who was a top strategist for Rauner’s 2014 governor campaign.

Watch for Pence — a former Indiana governor — to be helpful to Rauner.