CHICAGO (AP) - Gov. Pat Quinn's office has expressed confidence that a new plan to reduce the state's $100 billion pension shortfall will survive legal challenges.

The Friday statement was a response to a lawsuit filed in Cook County Circuit Court seeking to have the plan declared unconstitutional. It was filed Friday on behalf of a group of administrators and retired teachers

Quinn's office says it expects what it calls "this landmark reform" to be "upheld as constitutional."

It also contends the plan is "as constitutionally sound as it is urgently needed to resolve the...pension crisis."

The plan is estimated to save the state $160 billion, largely by cutting benefits for employees and retirees. The lawsuit says it violates a provision of the Illinois Constitution that says pension benefits may not be diminished.

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