Oral arguments on whether state law passed in 2013 will stand were held Wednesday before the Illinois Supreme Court.
The law reduces benefits for public employees like teachers, prison guards and many others.
State-employee unions object, citing a section of the state constitution -- Article VIII Section 5 -- which they say clearly prevents the state from taking such action.
Illinois Solicitor General Carolyn Shapiro, representing the state, disagrees.
"That is not what the clause says," Shapiro declared. "That is not what the clause is intended to do. That is not what the delegates to the Constitutional Convention discussed. And that is not how this court has ever read the clause."
Shapiro says that the state, in extreme circumstances, can change what it views as a contract with employees. She points to the state's budget problems as a reason.
Justice Robert Thomas asked whether the state created the emergency by low-balling pension payments.
"To respond to an emergency that, at least arguably, the state itself created... then aren't we giving the state the authority to modify its contractual obligations whenever it wants?" Thomas asked.
The state failed to contribute enough money for decades, which has led to the most underfunded system in the country.
Numerous amicus curiae -- friend of the court -- briefs were filed in the case, known as Doris Heaton et al vs. Pat Quinn et al by unions and by various entities whose employees would be affected by the law.
The court will consider the case. There's no indication when a ruling be announced.