Cliff Gardner, a Berkeley lawyer, filed the appeal Thursday, The Modesto Bee reported. Gardner, in a 470-page brief, said massive publicity about Laci Peterson's disappearance on Christmas Eve 2002, and the discovery four months later of her fetus and a day later her body in San Francisco Bay distorted the trial.
Peterson told police he found his wife, who was eight months pregnant, gone when he returned home from a fishing trip.
"It is probably fair to say that there are not many cases in the history of California where the state obtained a guilty verdict and death sentence for murder absent of how, where or when the murder occurred," Gardner said.
Investigators said the killing took place at the couple's home in Modesto in the Central Valley. The trial was moved to Redwood City, south of San Francisco, but Gardner said the change in venue was not enough to ensure the jury was not swayed by media coverage of the case.
Peterson, 39, has been on Death Row in San Quentin Prison since 2005.