SPRINGFIELD, Ill. (AP) -- Republican lawmakers are proposing a ban on closing any Illinois prisons until a study is done on the needs of the state corrections system.

Governor Rod Blagojevich wants to close a prison, even though state prisons now house about 35 percent more inmates than they were designed to hold.

Blagojevich first proposed shutting the Stateville prison in Joliet, but now he's targeting one in Pontiac.

Republican lawmakers said Thursday that Blagojevich seems to be picking prisons based on "whims." They say closing a prison is a serious decision that should be based on careful analysis.

They're calling for a study of prison needs that would be done in September 2009. They say no prison should be closed until the study is done.

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