Some of the state's biggest unions support the plan.
But, one group doesn't. The vice president of the Illinois Retired Teachers Association, Bob Pinkerton, says it's not constitutional. He made his argument to the Senate committee Wednesday.
He says it takes away guaranteed pension benefits and forces retirees to choose between two plans. Neither of which, he says, is very fair.
The group isn't just voicing its concerns over the bill. It's ready to take action too. Pinkerton says they will sue the state if necessary.
Supporters don't seem phased by the threat. They say this is the best plan out there right now, and believe, the way it's crafted, it could stand up in court.
The bill is one of two getting the most support. Lawmakers don't seem completely satisfied with either, so their could still be some changes made to one or the other.
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