By Nick Gale, WLS-AM 890 News

(JOLIET, Ill.) — Convicted wife murderer Drew Peterson lost another court battle Thursday when the Illinois State Supreme Court ruled that hearsay evidence used in the murder trial of his third wife Kathleen Savio did not violate his rights.

“This is the ultimate vindication of what we did in our 10 year struggle to convince the public against all odds that we had the evidence necessary to convict him of killing Kathleen Savio,” said Will County States Attorney James Glasgow shortly after the ruling was announced.

Peterson, a former Bolingbrook police officer, is serving 38 years for Savio’s death and another 40 years after being found guilty for trying to hire a hitman to take out Glasgow.

An attorney for Peterson says he’ll likely appeal the ruling.

With regards to the investigation into the disappearance of forth wife Stacy Peterson, Glasgow says the investigation is very much open and believes Peterson’s son Stephen may cooperate with the investigation.

“I’m talking about his change of attitude to open doors, and I’m not going to get into specifics but there is evidence that could potentially reach the level that we need to bring a charge,” Glasgow said. “I’m not saying that we’re going to be able to obtain it but it could be now, where as it wasn’t possible before.”

In an interview with the Chicago Tribune in January, Stephen Peterson revealed that he believes his father “probably” killed Savio and that he’s come to believe his father also killed Stacy.

“Over time, you hear enough (from police). They can’t all be full of s—,” Stephen told the Tribune. “I don’t want to come out and say he did it … but, I’m sure he did it.”

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