"That's correct, your honor, I'm innocent," Peterson told Judge Al Girolami, after he waived the reading of the indictment. Peterson had plead not guilty once before since his arrest in April.
Peterson, 31, was arraigned again because a judge last month said there was enough evidence for prosecutors to take the case to trial. He looked thinner during Wednesday's court appearance.
The hearing came a day after prosecutors for the first time hinted at parts of their theory behind the Laci Peterson slaying — saying Scott bled inside the truck he allegedly used to haul her body away after killing her.
Laci Peterson, 27, was eight months pregnant when she was reported missing last Christmas Eve. Her remains washed ashore in April a few miles from the area where her husband said he had gone fishing.
Assistant District Attorney Rick Distaso revealed that authorities believe Laci Peterson was killed at home, explaining why lawyers grappled at the preliminary hearing over a mop and bucket used to clean up the kitchen area in the couple's house.
Authorities believe her body was transported in the truck, then weighted down and tossed into in the San Francisco Bay.
In court papers, prosecutors said cement-like material was found in the bed of the pickup truck. A detective at the preliminary hearing said there was evidence Peterson fashioned several concrete anchors in his warehouse, but only one of those anchors was found in the boat he said he took fishing the day Laci vanished.
Prosecutors had refused to return Peterson's pickup truck because they believe it was used in the murder and wanted to keep it as evidence.
But on Wednesday, defense lawyer Mark Geragos, who is simultaneously representing Michael Jackson and earlier was counsel to accused shoplifter Wynona Ryder, persuaded the judge to order prosecutors to return the truck to his family. With legal bills mounting, the family has made $643 in monthly auto payments for nearly a year.
The judge said photos of the truck would be sufficient to show the evidence prosecutors claimed to have, CBS News Correspondent John Blackstone reports.
Girolami also refused to lift a gag order Wednesday or unseal any of the sealed court documents. A lawyer representing The Modesto Bee and four other newspapers had asked the judge to release police reports filed in support of arrest and search warrants.
Geragos had asked the judge to ease the gag order to allow him to respond to what the lawyer said were untrue statements about the case. Geragos hoped he could use the unsealed information "to try to stick a fork in some completely unfounded rumor or some piece of misinformation that, all of a sudden, seems to be a legend.
The judge scheduled a hearing for Jan. 6 so the defense can request that the trial be moved from Stanislaus County because of pretrial publicity in Laci Peterson's hometown.
Prosecutors are not convinced the intense media attention has made it impossible for Scott Peterson to get a fair trial in Modesto and want to survey potential jurors before any decision is made to move the trial.
The judge said he would rule on the change of venue motion before scheduling further hearings for the defense to challenge wiretaps, the use of devices that tracked Peterson and cadaver-sniffing dogs used to search for Laci Peterson's scent in the boat.