A judge has ruled against nearly all requests to retest evidence for DNA from convicted murderer Scott Peterson's defense team.
Peterson returned to court Wednesday in an ongoing bid for a new trial to clear his name.
Peterson, who was convicted more than 20 years ago of killing his wife Laci and their unborn son Connor, appeared in a Redwood City courtroom virtually from Mule Creek State Prison in Amador County, where he is serving a life sentence.
Peterson's team of lawyers with the L.A. Innocence Project filed several motions, including DNA testing of items gathered during the original murder investigation. Those items consist of a bloody mattress found inside a burned-out van found near the Petersons' Modesto home and a tarp found in San Francisco Bay near where Laci’s remains were found.
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The judge said the defense failed to prove why it needed to do new DNA testing on the evidence.
Although most of the motions were dismissed, the judge will allow for DNA testing of the tape found on Laci's pants when her remains were found.
Legal analyst Steven Clark talked about the defense’s strategy.
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"What the defense is asking for is access to evidence that previously had not been tested or was tested but today's tech is much more up to date," he said. "They want to establish an alternate theory: Could Laci Peterson have been alive when Scott Peterson went fishing?"
Prosecutors opposed the motions for DNA testing, saying they will not hand anything over unless ordered by the court.
The defense team said their fight to prove Peterson is innocent is not over and they "have a whole lot more."