Prosecutors have hinted that aside from his affair as a motive for murder, Peterson's business was struggling to stay afloat and he hoped to reap financial benefits from Laci Peterson's death.
But Martin Laffer, a certified public accountant and former Internal Revenue Service investigator, testified Monday that while Peterson's start-up fertilizer business was struggling, the parent company had assumed all debt and in fact had planned to lose money for the first four years.
Laffer then said the Petersons appeared in good financial shape.
He testified Tuesday that Peterson was paying $1,300 a month toward the mortgage on the couple's home, $50 more than the minimum required payment.
"If he was having financial problems, he would make the minimum payment," Laffer said.
"Does it appear to you that Scott and Laci Peterson were in financial trouble?" defense attorney Mark Geragos asked.
"Not at all," Laffer said.
"Does it appear to you they were doing well for a young married couple with a baby on the way at their age?" Geragos asked.
"Yes, they were fine," Laffer replied.
On cross-examination, prosecutor Dave Harris noted the Petersons had been selling jewelry at area pawn shops in the weeks before Laci vanished.
"Just the fact that somebody's selling something doesn't mean they need money," Laffer said, adding that based on his analysis of the same information examined by prosecution witnesses regarding Peterson's financial condition, "I reached a totally opposite conclusion."
A prosecution expert testified Peterson was in dire financial straights and desperately needed money.
On Monday, Laffer said Laci Peterson was also set to inherit several hundred thousand dollars from the estate of her grandparents. She had already inherited about $100,000 in jewelry after her grandmother's death.
Because the funds are now being split between two of Laci's siblings, Laffer said Peterson would have reaped the financial benefits from the inheritance only if Laci were still alive and the two were married.
Defense attorneys began their case Monday by attacking a key prosecution theory that Peterson lied about a crucial element in the investigation when he told police he used cement mix to repair his driveway.
Prosecutors claim Peterson made five cement anchors, one of which was found in the boat authorities allege he used to dispose of his wife's body. The others, which they allege he used to sink his pregnant wife's body in San Francisco Bay, have not been discovered.
Peterson told police he made only one anchor and used the remainder of the 90-pound bag of cement to repair his driveway.
However, a prosecution witness testified the concrete samples taken by police from Peterson's driveway were not from the same mix that made the anchor.
But Steven Gabler, a concrete expert asked by the defense to examine their own samples taken from Peterson's driveway, testified Monday the samples were indeed a match with the anchor.
"They're all consistent ... with each other," Gabler said.
Prosecutors allege Peterson killed his pregnant wife, Laci, on or around Dec. 24, 2002, then dumped her body in the bay. The bodies of Laci Peterson and the fetus she carried washed up about four months later, a few miles from where Peterson claims to have been fishing alone the day his wife vanished.
Defense lawyers claim someone else abducted and killed Laci, then framed their client after learning of his widely publicized alibi.
Meanwhile, there were signs defense attorneys were preparing Peterson for possible testimony.
Attorney Michael Cardoza, a former prosecutor who has sat in on the trial as a legal analyst, said Monday he was asked by the defense to cross-examine Peterson in two mock sessions last week.
"I gave him no advice," said Cardoza, who added that he took no money for the work and still serves as a legal analyst.
Throughout the trial, reports CBS News Correspondent John Blackstone, Cordoza has been close to both the Peterson family and to defense attorney Mark Geragos, who invited Cordoza to question Peterson and who watched the session.
"When I was through, I left. The decision to put him on the stand will be the defense's," said Cordoza.
But most trial observers see almost no chance Peterson will testify.
"I don't think that Mr. Geragos would be so foolish as to put Scott Peterson on the witness stand," said Gloria Allred, the attorney for Peterson's ex-girl friend Amber Frey. "And I think it's just a public relations stunt to try to suggest that there is even any possibility at all that he would take the witness stand."
Court TV's Beth Karas says one reason for a mock cross-examination is to show the defendant why he should not take the stand.
"In this case, I suspect that it's Scott Peterson who wants to take the stand and his defense team thinks that he probably shouldn't," Karas said on CBS News' The Early Show. It may be that "they wanted to see how he would do on cross-examination to prove to him that he does not have an answer for all of the questions, just like he didn't have an answer for all of the questions when the police were asking him questions, when the media were interviewing him.