Peterson was convicted earlier this month of murdering his pregnant wife, Laci, and the fetus she carried. Jurors were scheduled to begin hearing testimony Tuesday as to whether he should get life in prison or death. A judge will issue the final sentence.
The penalty phase will be like a mini trial, reports CBS News Correspondent Steve Futterman. Both the prosecution and defense will make opening statements, then witnesses will take the stand. Testimony is likely to be emotional, with the prosecution expected to call relatives and friends of Laci Peterson to talk about their loss.
"This will be incredibly emotional testimony," said CBS News Legal Analyst Trent Copeland. "It will come from the heart of these victims, it will be emotional, heartfelt, and I think it will really touch the raw emotions of this jury."
The defense will call relatives and friends of Scott Peterson, who will essentially be pleading for his life.
"I would say it's going to be hard a hard job to save this man's life," said former district attorney Terence Hallinan. "If Geragos can do that, I would say it's a win for him."
When Peterson's conviction for the murder of his wife Laci and unborn son was greeted with cheers outside the Redwood City courthouse, defense attorney Mark Geragos said it was proof Peterson couldn't get a fair trial here, reports CBS News Correspondent John Blackstone. A lower court judge, and subsequently, denied his motion.
In its ruling Monday, the California Supreme Court rejected the petition to select a new jury and delay the penalty phase of the trial.
Peterson was convicted on one count of first-degree murder in the death of his pregnant wife, Laci, and one count of second-degree murder for the killing of her fetus.
In his appeal for a new jury, Geragos also cited the ousting of two jurors during deliberations. Both ex-jurors remain bound by a gag order.
"The most sympathetic people in this case at this point are the two mothers, and no matter how you feel about Scott Peterson, you do feel bad for Jackie Peterson," said CBS News Legal Analyst Wendy Murphy on The Early Show. "I think there is no question that Sharon Rocha [Laci's mother] is going to be the star of the show."
But Murphy, a former prosecutor, doesn't expect to hear from Scott Peterson.
"There is no chance he's going to take the stand. What can he say? 'I cannot confirm or deny whether I'm guilty. But let me tell you what a nice guy I used to be?' He can't help himself," she said.
Defense attorney Mickey Sherman, also a CBS News Legal Analyst, disagrees.
"I personally think he should testify," Sherman said. "He doesn't have anything to lose."
Meanwhile, the judge ruled Monday that jury instructions and the reading of the panel's sentence recommendation will be broadcast live on an audio feed. The judge will also allow still pictures of Peterson while he issues his instructions.