During her first few minutes on the witness stand, Sharon Rocha held herself together. Then prosecutor Rick Distaso asked her about the last time she spoke with daughter Laci. "She told me that...," Rocha began, pausing as her voice started to crack, "on the 23rd..." On the verge of breaking down, Rocha looked up at Judge Alfred Delucchi. "I'm okay," she said softly. After another pause she continued, "On the 23rd I spoke to her." It was a heartbreaking moment in the first week of Scott Peterson's murder trial but, from the prosecution's perspective, a necessary one. "You've got to have some drama in a murder case," says Michael Cardoza, a defense attorney in the San Francisco area. "Jurors expect that." One of the most dramatic moments so far: the June 8 testimony of Rose Rocha, Laci's sister-in-law, who recalled going up to Scott in May 2002 and asking whether he was looking forward to fatherhood. Scott's startling response: "I was hoping for infertility."

The Rocha and Peterson families seem determined to bear their burdens stoically. The Rochas enter the court first and take their seats near the jury box. A few minutes later the Peterson camp—usually Scott's parents, Lee and Jackie, and sister-in-law Janey—seat themselves behind the defendant. The families rarely make eye contact. One day as he passed by his son, Lee asked, "How are you?" Scott, who has let his hair grow out and wears a baggy suit, answered with a beaming smile, "I'm good."

The consensus among legal experts is that the defense has gotten off to a strong start. In his opening statement Distaso mentioned that when Scott was interviewed by police after reporting Laci missing on Dec. 24,2002, he insisted that on that morning he and Laci had watched Martha Stewart on TV as she prepared a meringue. According to Distaso, the program had aired on Dec. 23, suggesting that Scott couldn't get his own story straight.

But the next day that argument fell flat when Peterson attorney Mark Geragos played a tape of the Dec. 24 segment; Stewart did, in fact, whip up a meringue. An insignificant detail perhaps, but the gaffe could suggest to the jury, says Ruth Jones, a professor at McGeorge Law School in Sacramento, that "if [the police] couldn't even check something like this out, you can't trust them with the rest of the case."

It is worth remembering that this trial could go as long as six months. "The prosecution will have good days and bad days, as will the defense," says Jones. "If you're lucky, the bad days come at the beginning, because what will the jury remember? Good days at the end are always the best."

Bill Hewitt. Ron Arias, Frank Swertlow, Vickie Bane and Lyndon Stambler in Redwood City

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