Two days before Scott Peterson is to be sentenced, his attorneys have filed a motion for a new trial.
The attorneys claim that newly discovered evidence withheld by the prosecution could have brought a different verdict.
The 135-page motion seeks a new trial based on new evidence, legal errors, misdirection of the jury, jury misconduct, evidentiary issues and “insufficient evidence to support the jury's verdict of guilt.”
The jury recommended the death penalty for Peterson, and formal sentencing is set for Wednesday.
According to the defense motion, prosecutors withheld key evidence that a state prison inmate claimed to have information about Laci Peterson's disappearance.
The inmate said he was told the pregnant schoolteacher had interrupted a burglary at a neighbor's home.
The defense says that mention of the inmate's claim was buried in thousands of pages of discovery.
In their reply, prosecutors suggest that the defense simply missed the details in his haste to take the case to trial.
Peterson was convicted in November on two counts of murder in the deaths of his pregnant wife, Laci, and the fetus she carried.