The clause that could be worth billions will be heard in the state’s high court Wednesday.
The State Supreme Court will hear about a recent measure to reform pensions in Illinois. The law, commonly referred to as SB 1, mandates an increase in how much the state funds employee retirements while cutting the cost-of-living increases moving forward for state retirees.

Reform supporters say that would save the state and taxpayers billions of dollars over many years, but unions representing retirees filed suit in lower courts saying the law is an unconstitutional diminishment of benefits.

The state says the extraordinary debt, which is nearly a quarter of every dollar the state spends, is taking away from other vital state services and the change is necessary.

The court is expected to rule sometime before the end of the current fiscal year.