CHICAGO (CBS) — The Illinois Supreme Court has agreed to hear the appeal the murder conviction of former Bolingbrook cop Drew Peterson.

Peterson is serving a 38-year sentence for killing Kathleen Savio in 2004.

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Although her death initially was ruled an accident, authorities reopened the case after Peterson’s fourth wife, Stacy, disappeared in 2007.

Savio’s body was exhumed, and a new autopsy ruled Savio’s death a homicide by drowning.

In 2012, a Will County jury convicted Peterson of drowning Savio in her bathtub. Prosecutors had argued he killed her to prevent her from testifying against him in divorce proceedings.

Peterson appealed his conviction and sentence, arguing prosecutors did not prove him guilty beyond a reasonable doubt, his trial attorney operated under a conflict of interest, and he was denied effective counsel. He also said he was denied a fair trial due to numerous errors by the trial judge.

A three-justice panel of the Third District Illinois Appellate Court upheld Peterson’s conviction in November, stating the evidence against him was sufficient to prove he killed Savio.

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In a unanimous opinion, the court said it found no errors at trial, and that the physical and circumstantial evidence presented in court proved Peterson was the killer. The justices also rejected Peterson’s claim that his lead trial attorney, Joel Brodsky, had a conflict of interest due to media contracts he signed before trial.

CBS 2’s Suzanne Le Mignot spoke with Peterson’s attorney Steve Greenberg, who said he hasn’t yet spoken with his client.

“I talked to his son, his son was obviously ecstatic,” Greenberg said. “I’m working to get a message down to Drew. I know he’ll be thrilled to hear that someone’s finally gonna hopefully consider whether or not he got a fair trial.”

When asked about what some of the key things the Supreme Court may have looked at in deciding to hear the appeal, Greenberg said, “Well, there’s the statements from Kathleen, from the grave, where she predicted the future, which are clearly improper. There’s the hearsay testimony from Stacy, the ineffective assistance, where the lawyer said that Stacy knew Drew had committed the crime. You never would call someone to hang your own client and then there’s the media rights contract, where the lawyer was profiting from the sensationalism of the case, which wasn’t in the best interest of the client.”

The Kathleen Savio case was reopened after Peterson’s fourth wife Stacy disappeared in 2007. Peterson is still a suspect in that case.

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This coming May, Peterson will go to trial in another case. He’s charged with soliciting an inmate to kill Will County State’s Attorney James Glasgow. Glasgow prosecuted the Savio case.