(WGN-AM)- A recently enacted state law written to allow the use of beyond-the-grave hearsay evidence against Drew Peterson should be declared unconstitutional, according to a motion that Peterson's attorneys are expected to file today.

"The new hearsay law ... would allow gossip, innuendo, rumor and back fence scandal to come into court and masquerade as evidence," the motion states. The motion is posted on the Web site of Peterson's attorneys.

The hearsay law would allow Will County State's Atty. James Glasgow to use statements purportedly made by Kathleen Savio, Peterson's third wife, at Peterson's trial for allegedly murdering her. Savio, who was divorcing Peterson, was found drowned in an empty bathtub in her home on March 1, 2004. An initial autopsy ruled her death an accident, but after the disappearance of Peterson's fourth wife, Stacy Peterson, another autopsy declared Savio's death a homicide.

"Having a newly minted homicide, but not having evidence to prosecute anyone for it, the Will Couny State's Attorney decided to draft a new law," the motion asserts. That law "would allow him to introduce otherwise inadmissable evidence against Drew Peterson."

Reportedly, Savio had told her sister and others that Peterson, then a Bolingbrook police officer, had threatened her and that she feared for her life.

The motion also attacks the fact that the hearsay law can be used in cases in which a crime predates passage of the law, pointing out that ex post facto laws violate the state and U.S. constitutions.

(The Chicago Tribune contributed to this story)

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