Updated

Scott Peterson's (search) lawyers said in court papers unsealed Monday that newly discovered evidence could have spared the former fertilizer salesman from a death sentence in the slaying of his pregnant wife.

The motion, filed under seal Feb. 25 in Redwood City, requested a new trial based on evidence allegedly withheld by prosecutors and improperly presented, along with legal errors and jury misconduct.

Defense lawyer Mark Geragos (search) said prosecutors withheld evidence that a state prison inmate claimed he heard that Laci Peterson (search) had interrupted a burglary at a neighbor's home in Modesto on Dec. 24, 2002 — the day she disappeared. Scott Peterson claims he went fishing that day, and Geragos says the tip "points to the conclusion that Laci was alive after Scott left for the day."

But prosecutor David Harris the burglary happened two days after Laci Peterson's disappearance. He said the evidence would not have changed the verdict.

Geragos said he became aware of the tip about six weeks before the verdict and later discovered "a small notation in hundreds of pages of tip sheets" provided by prosecutors before the trial.

He said it took several weeks to investigate and prison tapes that would have confirmed the tip were no longer available.

"If the evidence were presented at a retrial, it is highly probable a different result would have occurred," Geragos wrote.

Harris said the tip was provided to defense attorneys a year before the trial started. "His claim is reminiscent of the 'boy who cried wolf,"' Harris said.

The defense also claimed the judge erroneously dismissed two jurors, and erred in denying Geragos' motion for a second change of venue.

Peterson, 32, was convicted Nov. 12 of two counts of murder in the deaths of his wife and her fetus. The jury recommended the death penalty a month later; formal sentencing is set for Wednesday.