JOLIET, Ill. (AP) - Drew Peterson's son stepped up Wednesday as the last witness before the defense rested, telling jurors in a calm, confident voice that he never for a second believed that his father killed his mother.
Shortly after the 19-year-old child of the former suburban Chicago police officer and his third wife, Kathleen Savio, testified, Drew Peterson stood in the Joliet courtroom to say he had decided not to take the stand.
Dressed in a suit and tie, Thomas Peterson, a Bolingbrook High School valedictorian last year and now a University of Pennsylvania student, smiled at jurors and seemed at ease as he repeatedly defended his father.
"I believe that my dad is innocent," he said firmly when a defense attorney asked why he was in court.
Asked by defense attorney Joel Brodsky if he was there to support his father, he answered politely, "Yes, sir."
Drew Peterson, 58, has pleaded not guilty to first-degree murder in Savio's 2004 death, which was initially ruled an accident. Her death was reclassified a homicide only after his fourth wife, Stacy Peterson, disappeared in 2007.
Just before the defense rested, Judge Edward Burmila asked the former Bolingbrook police sergeant whether he would take the stand.
"I will not testify," he said firmly.
The next step will be for prosecutors to put on a rebuttal of the defense case, recalling some witnesses and possibly calling new ones. That is expected to happen Thursday.
Testifying would have opened Drew Peterson to a blistering and potential damaging cross-examination. His well-spoken son cut a sympathetic figure.
Thomas Peterson was 11 when his mother was found dead in her bathtub with a gash on the back of her head. At the time, he and his brother were staying with Drew and Stacy Peterson just blocks from Savio's house.
Thomas Peterson told jurors he saw no change in his father's demeanor around the day his mother died.
"There was nothing out of the ordinary," he said. "I would remember if there was."
He said that when his father broke the news about their mother's death to them, he seemed genuinely distraught.
"I have never seen someone so shaken," Peterson told jurors.
In a high-risk move earlier Wednesday, defense attorneys put on the stand a divorce attorney who had spoken by telephone with Stacy Peterson about her plans to divorced Drew Peterson three days before she went missing.
Harry Smith told jurors Stacy Peterson was considering a possible shakedown of her husband by threatening to tell police he killed Savio, which the defense hoped would dent the credibility of hearsay evidence related to her.
"She said, 'If we threatened to do this, could we get more money?'" Smith testified.
Stacy Peterson's pastor testified for the state earlier that she told him how Drew Peterson mysteriously disappeared from the house one night around the time Savio died.
But Smith's testimony also emphasized that Stacy Peterson seemed convinced her husband did kill Savio. And it also risked raising the question in jurors' minds about what happened to Stacy Peterson.
The judge has barred any mention to jurors about her disappearance or that she is presumed dead. But Smith came close to broaching that issue when he said Stacy Peterson never got around to hiring him. When Brodsky asked why, Smith stammered, understanding the answer would be inadmissible. After a break, Brodsky withdrew the question.
Another time, Smith said, he told Stacy Peterson during the phone conversation that she should "be careful" - an apparent reference to how Drew Peterson could do her harm. When Brodsky said Smith had previously testified that he told her to be careful because she could be arrested for attempted extortion, the witness denied it.
"I did tell her to be careful, but it wasn't about extortion," he said. He didn't elaborate.
Some courtroom observers said later that the defense blundered by putting Smith on the stand.
"It was a gift from the defense," said Pam Bosco, a spokeswoman for the Stacy Peterson family who has attended nearly every day of the 5-week-old trial.
Bosco said Stacy Peterson grasped that what she knew about Savio's death gave her leverage to break free of Drew Peterson and ensure she would get custody of their two young kids.
"This was her way out," she said about Stacy Peterson. "Three days later she's dead - not disappeared: dead."
Drew Peterson is a suspect in her disappearance but has never been charged in her case.
In comments to reporters later Wednesday, Brodsky stood by the decision to call the divorce attorney.
"We have now given a motive for Stacy to fabricate (her claims that her husband killed Savio)," he said.
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