SPRINGFIELD — Illinois officials have 20 days to explain what steps the state is taking to get union workers their past due step increases.

The Illinois Labor Relations Board issued the decision this week in the ongoing case of members of the American Federation of State, County and Municipal Employees trying to get step raises owed to members as far back as 2015.

Gov. Bruce Rauner’s administration stopped paying step increases after AFSCME’s old contract with the state expired June 30, 2015. However, AFSCME contended the administration could not do that because the provisions of the old contract continued while a new one was being negotiated. The issue ended up in court and the courts ruled that AFSCME members are entitled to continue receiving step increases.

The ILRB decision said that AFSCME members who were denied step increases in recent years must receive them along with 7 percent per year interest on the amount they are owed.

The decision says that the state must “notify the Board, in writing, within 20 days of the date of this order, of the steps that the (state) has taken to comply...”

“Typically when an employer has been so clearly found in violation of the law, they comply with the board’s order voluntarily and we expect the state to do so,” said AFSCME spokesman Anders Lindall. “If it doesn’t, we will be prepared to immediately file a petition for compliance.”

That, in turn, would start a 75-day clock for a compliance officer appointed by the ILRB to respond, he said.

The Department of Central Management Services did not respond to a request for comment.

Step increases are automatic raises given to workers in the first seven to 10 years of their careers. AFSCME said about 15,000 of its members are eligible for them.

The cost of making good on those step raises has been pegged at about $415 million. State lawmakers did not appropriate money for the step increases in the budget that went into effect July 1.

The step increases are separate from back pay owed to union workers dating back to 2011 when then Gov. Pat Quinn said lawmakers didn’t appropriate money to cover raises called for in union contracts. Lawmakers did include about $63 million in the budget to finally pay those back wages.

Lindall said that none of the back wages have yet been paid, despite the appropriation. The Rauner administration did not respond to questions about back pay.