JOLIET, Ill. (CBS) -- Former Bolingbrook police sergeant Drew Peterson on Thursday was found guilty of murder in the 2004 death of his third wife, Kathleen Savio.
A jury of seven men and five women had deliberated since 9:37 a.m. Wednesday morning before reaching a verdict around 2:30 p.m. Thursday.
Peterson, who has been jailed since May 2009, was stoic as the guilty verdict was read, but audible gasps could be heard in the courtroom. He is scheduled to be sentenced Nov. 26 and faces a range of 20 years to 60 years in prison.
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Peterson was charged with killing Savio in her bathtub on March 1, 2004, as they were going through a divorce. Initially, the Will County Coroner's office ruled Savio's death an accidental drowning. But her death was reclassified as a homicide after an exhumation and a new autopsy, following the disappearance of Peterson's fourth wife, Stacy, in October 2007.
"Game over, Drew," Cassandra Cales, sister of Stacy Peterson, told reporters after the verdict. "He can wipe the smirk off his face. It's time to pay."
Peterson's defense team vowed to appeal. They had long criticized the prosecution's use of hearsay evidence, which effectively allowed Stacy Peterson to speak from beyond the grave and incriminate her husband in Savio's death. State lawmakers passed legislation that allowed the hearsay evidence at trial.
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"You know what they say: A conviction is a first step in a successful appeal," Joel Brodsky, Peterson's lead defense attorney, said.
Brodsky said Peterson was philosophical when he talked with his client earlier Thursday. "Drew said to me, 'Whatever the verdict, we did the greatest job we could,'" the attorney said.
Peterson's attorneys conceded the former police sergeant is an unpopular figure.
Jurors said they would not talk with the media, but released a collective statement through a Will County sheriff's spokesman.
"We would like to thank Judge Burmila, the bailiffs and the Will County Sheriff's Department for the duration of this trial," the statement said. "We have taken the responsibility bestowed upon us by the court with a great deal of solemnity and diligence. After much deliberation, we have reached a decision we believe is just."
Family members of Savio were emotional but elated at the verdict.
"I'll never have my sister again -- I still have to visit her at the cemetery -- but at least I know she got justice," Nick Savio, Kathleen Savio's half-brother, told reporters outside the Will County Courthouse.
Investigators believe Stacy Peterson is dead, and have named Drew Peterson as a person of interest in her disappearance. He has not been charged with a crime in that case.
Pam Bosco, a spokeswoman for Stacy Peterson's family, said a second prosecution is coming.
"Stacy's case is right around the corner -- I truly believe that," said Bosco, who thanked the jury members for their decision.
Will County State's Attorney James Glasgow agreed prosecutors are reviewing the disappearance of Stacy Peterson "with an eye to charging it."
He called Thursday's guilty verdict "transcendental."
"It transcends the criminal justice system," Glasgow said. "It makes a statement about violence against women that is one of the biggest problems that we have in this country -- and that it won't be tolerated."
He called Drew Peterson a "coward and a bully."
Earlier Thursday, jury members sent trial judge Edward Burmila a note, asking, "Just to be clear judge, what does unanimous mean?"
The judge replied to them: "The word unanimous has its common meaning. It indicates the agreement of all on the matter at hand, and your verdict must be unanimous and signed by all."
The atmosphere at the courthouse was circus-like. A group of regular Peterson trial spectators even prepared a song about Drew Peterson's conviction, sung to the tune of "Puff the Magic Dragon."
It went, in part:
Drew the lady killer, won't be getting out of jail
Who'd of thought a few weeks ago that justice would prevail?
Once a respected police man, sworn to protect and serve,
He'll be in jail for 20-plus. He got what he deserved.
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