Former Bolingbrook police sergeant Drew Peterson rocked an Illinois courtroom on Thursday when he screamed out his innocence before a judge sentenced him to 38 years in prison for the 2004 drowning death of his third wife, Kathleen Savio.
"I did not kill Kathleen!" the normally cool Peterson shouted into a courtroom microphone from the witness stand.
Without missing a beat, his dead wife's sister, Susan Doman, shouted back, "Yes, you did! You liar!" before the judge ordered sheriff's deputies to remove her from the courtroom.
"I wasn't going to take the devil. I wasn't going to let him say that," Doman later told reporters.
In the long statement on his innocence, Peterson blamed Will County State's Attorney James Glasgow for what he described as an obsessive investigation. In tears at times, Peterson told the court he was being sentenced to the Department of Corrections to die.
"I think the only thing left to make this case more true to form would be cruel and unusual punishment," he said. "I don't think anybody would care, because nobody cares. I can't believe I spent 32 years protecting the constitution that allowed this to happen to me."
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He took issue with a law passed by the Illinois General Assembly in in July 2009 that allowed hearsay to be admitted as evidence in cases where prosecutors believe the victim was killed specifically to prevent them from testifying. The law was dubbed the "Drew Peterson Law."
"Hearsay is a scary thing," Peterson told the court. "It requires no proof of truth. Anything can be said and no one is accountable."
He said the statements made against him were from "women trying to better position themselves in a divorce. ... Everybody lies in a divorce."
Still, he said he loved his ex-wife.
"She was a good mom," he said, tearing up. "She did not deserve to die. But she died in an accident."
Glasgow thought little of Peterson's statement but said the emotional outburst exposed the real Drew Peterson -- the one capable of murder.
"We all got an opportunity to see a psychopath," said Glasgow. "When he got up on the stand and that shrill, kind of feminine screech that he didn't kill Kathy, that's the guy that killed Kathy. You got a glimpse into his soul."
Peterson was found guilty in September of murdering Savio. Her death was initially ruled an accident, after neighbors found the 40-year-old aspiring nurse's body in a dry bathtub at home. It was Stacy Peterson's 2007 disappearance that prompted authorities to take another look at Savio's death and eventually reclassify it as a homicide. Drew Peterson is also a suspect in the disappearance of Stacy Peterson -- who was 23-years-old when she vanished -- but he hasn't been charged in her case.
Thursday's ruling came just a couple hours after Judge Edward Burmila denied a motion by defense attorneys to give the former cop a new trial and essentially means Peterson, 59, will spend the rest of his life in custody. The judge gave Peterson four years' credit for the time he has served since his 2009 arrest.
Illinois does not have a death penalty.
"I pray that during the last minutes of his life, he is able to clearly see her and she is watching his descension into hell," Savio's brother, Henry, told the judge.
Peterson's attorneys vowed to wage an appeal.
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"We all have some very viable issues. We're putting our big boy pants on, we're going to go with these issues, and we're going to be back here. We're confident of that,' said attorney John Heiderscheidt.
In two days of testimony, Peterson's current legal team argued for a new trial alleging the former lead attorney, Joel Brodsky, botched the first trial by calling divorce attorney Harry Smith to the stand.
Smith testified that Peterson's fourth wife, Stacy Peterson, told him her husband killed Savio and that he warned Stacy she had to tell someone. Several jurors said that bombshell testimony led them to convict Peterson.
During the sentencing hearing Savio's sister, Anna Marie Savio-Doman, asked the judge to give her sister "justice, once and for all."
"One of the hardest things for me is knowing the pain and fear that Kathleen must have suffered at the time of her murder," Doman said. "The horror and betrayal she must have felt when she realized that someone she had trusted and loved more than anything was actually killing her."
Henry Savio said Peterson terrorized his sister, brutalized her and drowned her.
"I will be mending my family, including my family's relationship with Kitty's children, while he is rotting in jail for the rest of his life," he said. "While he is in jail, I hope that Kitty is what he sees every night before he sleeps and I hope that she is haunting him in his dreams."
"He took Kathleen's future and now she has taken his."
NBC Chicago's Kim Vatis, Lauren Jiggetts, Lauren Petty, Courtney Copenhagen, Lisa Balde and BJ Lutz contributed to this reported. Additional reporting by The Associated Press.