A California judge on Wednesday ruled that only one item from a list of evidence collected in the case of a man convicted 20 years ago of killing his pregnant wife should undergo new DNA testing.

The Los Angeles Innocence Project argued in court that several pieces of evidence were suppressed in Scott Peterson’s trial. However, the judge ruled that only a piece of duct tape found on Laci Peterson’s pants should be re-tested.

The defense had argued the tape contained human DNA that could point to someone other than Peterson as the perpetrator in his wife’s death. A hearing is scheduled for July 1 to discuss the testing stipulations.

Prosecutors had pushed back on the testing requests by telling the court that the evidence was already tested in 2019, but Peterson’s attorneys maintained that the limited testing offered inconclusive results.

They had also sought new testing on a bloody mattress discovered in a burnt-out van the day after Laci disappeared.

The judge ruled that testing in 2019 showed there was no blood on the mattress cloth that Peterson’s team requested undergo new testing. The judge also agreed with the prosecution’s argument that the van was not related to the Peterson case and that the defense failed to prove it was.

Similarly, the judge ruled that the defense failed to prove that items found in the vicinity of where Laci Peterson’s body washed ashore were directly associated with her and her unborn child.

The judge said a glove and hammer found in the home of one of the Petersons’ neighbors were never in police custody and therefore did not qualify for retesting.

A jury found Peterson guilty in the death of his wife, who was eight months pregnant with their son when her body washed ashore. Prosecutors at the time asserted that Peterson faked her disappearance to cover up that he dumped her body in the Berkeley Marina on Christmas Eve in 2002.

He was initially given the death penalty, but the California Supreme Court overturned the sentence in 2020. He was resentenced to life in prison without the possibility of parole.

Peterson has always maintained his innocence, and his trial defense suggested that Laci was killed after stumbling upon a burglary.

Last year, he petitioned to be seen by a judge based on new evidence and potential juror misconduct, arguing one of the jurors hid details and had been untruthful about her personal life.

Peterson’s legal team argued the juor’s failure to disclose she had been a victim of domestic abuse led to “prejudicial misconduct.” The woman co-wrote a book about the case with other jurors and has denied that she was influenced by her personal experiences.

Peterson was previously denied a new trial in 2022 based on the juror misconduct claim. Superior Court Judge Anne-Christine Massullo ruled that although the woman made false statements in her juror questionnaire, the answers were the result of “a combination of good faith misunderstanding of the questions and sloppiness in answering.”

The Los Angeles Innocence Project, known for its mission to exonerate the wrongly convicted, has taken on Peterson’s case.

The nonprofit organization filed for post-conviction discovery as well as the request for new DNA testing in an effort to have Peterson’s conviction overturned.

This article was originally published on NBCNews.com