Peterson Defense: Scanty Evidence

Scott Peterson's defense lawyer attacked the case against his client Wednesday as flimsy and circumstantial, saying the fact that the former fertilizer salesman had a mistress didn't mean he killed his pregnant wife.

"He's not charged with having an affair," defense lawyer Mark Geragos told jurors. "The fact of the matter is that this is a murder case and there has to be evidence."

Geragos seized his first chance to contradict the portrait prosecutors painted of Peterson a day earlier — that of a lying cheat whose affair with massage therapist Amber Frey drove him to murder.

At times breaking his serious tone to pepper his presentation with jabs at authorities who arrested Peterson, Geragos offered innocent explanations for his behavior after Laci Peterson's disappearance.

Assistant District Attorney Rick Distaso detailed Peterson's extramarital affair with Frey and played tapes of Peterson telling Frey he was in Europe when he was actually at a vigil for Laci. Then there were conflicting accounts of his whereabouts the day of the crime, telling some he played golf, others he was fishing.

Geragos downplayed Peterson's interest in Frey, saying they only went out on a few dates.

"Their theory would be that Scott didn't want to have a child," Geragos said. "He didn't want to have a relationship and he was therefore going to chuck his entire life with Laci ... for this woman he had two dates with."

Geragos characterized Peterson as a giddy expectant father who accompanied his wife to all her doctor's appointments.

"Mark Geragos has an uphill battle to change perceptions about his client and I think he's off to a good start. His opening statement makes sense with what he has to deal with; he's not telling jurors that his client is a saint, he's just telling them that a cheating husband isn't necessarily a murdering husband," says CBSNews.com Legal Analyst Andrew Cohen.

"This is going to be a case in which the side that answers the most questions on the minds of jurors likely will win. There are plenty of questions about the prosecution's case and there are plenty of questions about Scott Peterson's conduct and I think we're seeing during opening statements the battle over how those questions get framed," says Cohen.

Distaso didn't promise jurors anything about a murder weapon or an eyewitness to the crime, and Geragos dwelled on the circumstantial nature of the prosecution.

Authorities in the couple's hometown of Modesto collected more than 100 bags of evidence and state crime lab scientists analyzed the evidence exhaustively, Geragos said.

"What did they get out of all those tests? Zip, nada, nothing," he said.

As he has since Peterson's arrest more than a year ago, Geragos also argued that authorities ignored important leads that could exonerate his client.

Peterson, 31, could face the death penalty or life without parole if convicted in a trial that is expected to last six months.

Much of Distaso's methodical presentation Tuesday focused on Peterson's relationship with Frey, the woman to whom he read Russian poetry and promised "our relationship will grow" even as she was recording their telephone conversations for police. Peterson also told Frey he didn't want to have children and was considering a vasectomy, Distaso said.

Prosecutors allege Peterson killed his wife on or around Dec. 24, 2002, and dumped her body in San Francisco Bay using a recently purchased boat.

Peterson gave conflicting accounts of his whereabouts on that day and brushed off in-laws who were helping to search for Laci Peterson, who was eight months pregnant with a boy the couple planned to name Conner, prosecutors said.

The bodies of Laci Peterson and her fetus washed ashore in April 2003, near the marina where Peterson says he set out on a solo fishing trip the morning his wife vanished.

Distaso told jurors that from the moment Peterson called his mother-in-law on Christmas Eve and said he had returned from fishing to an empty house, things didn't make sense.

When family members joined police to investigate Laci Peterson's disappearance, their search first focused on a park near the couple's home, where she used to walk the family's dog.

When Sharon Rocha, Laci Peterson's mother, saw Scott Peterson in the park, her questions were met with what Distaso characterized as terse indifference, the prosecutor said.

"'What's going on? Where were you fishing?'" Distaso said Rocha asked. "She's getting these one-word responses."

Peterson then wandered off, he said.

Distaso ticked off what he implied was double-talk that exposed Peterson's duplicity, saying that while Peterson told Rocha he had been fishing, he later told Laci Peterson's uncle and two neighbors he had been golfing.