VISALIA, Calif. (KFSN) -- Accused Golden State Killer Joseph DeAngelo will be back in court in April.
The Tulare County District Attorney's Office has charged him with the murder of a Visalia professor.
Now, they say they've ruled him out for the murder of a Exeter teen that same year.
As part of the conviction review process, members of the Tulare County District Attorney's Office reviewed hundreds of pages of reports, transcripts, and evidence, took a trip to Sacramento, and even listened to the popular 12-26-75 podcast.
Its creators claim Oscar Clifton, now dead, did not kill Exeter teen Donna Richmond in 1975.
Clifton was convicted of her murder in 1976 and filed many appeals in the years to follow-with no success.
The podcast creators believe the Visalia Ransacker, who authorities say is also the accused Golden State Killer Joseph DeAngelo, was responsible for Richmond's violent death-she was strangled, beaten, and stabbed.
Her body found in an orange grove near the Friant-Kern canal.
They also think DeAngelo killed Visalia teen Jennifer Armour in 1974.
DeAngelo was working as an Exeter Police Officer at the time.
The Tulare County Sheriff's Office says DeAngelo and Clifton are persons of interest in Armour's case.
But through the conviction review, the DA's office still believes Clifton killed Richmond.
"We feel that Mr. Clifton received a fair trial, and that the evidence more than sufficiently points to his guilt," said Tulare County District Attorney Tim Ward.
After DeAngelo was arrested last year, his DNA profile became available for analysis.
So the DA's office compared it to a partial DNA profile developed in 2011 from semen found on Richmond's body.
"A partial profile, so really-can somebody be excluded?" said Tulare County Assistant DA David Alavezos. "And in this case, if you don't match at the locations of the DNA chain and DeAngelo did not, that person is excluded."
In response, the creators of 12-26-75 argue that DeAngelo cannot be excluded as a contributor based on the 2011 testing, saying:
"Neither the lab, nor the Tulare DA have any idea where those three alleles in the wash came from: the contaminated mixing fluid; lab worker or sample contamination when the slide was cut or mounted; skin cell DNA from the scotch tape; or, spittle from one of the officers on the scene, at autopsy or the mortuary workers who took Donna from the grove to the funeral home prior to autopsy. What we do know, is those alleles did not come from semen. It was determined in the lab there was no semen on the hairs before they were put into the wash fluid for DNA testing."
The podcast creators have other arguments in defense of Clifton-they say he had an alibi, and that alibi witnesses were suppressed during the trial.
But for now, the DA's office considers the case closed.
"We're going to look at what we have in the evidence," Alavezos said. "Is there anything new that would tell us that this person either couldn't or might not have done the crime, and we didn't find that."
The district attorney's office also says the partial profile was compared to Clifton's DNA profile in 2011.
They determined he could not be excluded as a contributor.
"Despite the allegation that the sample analyzed did not contain semen, the trial transcript is clear that there was in fact semen on the evidence collected from Donna Jo Richmond's body," Alavezos said. "The partial DNA profile was clearly identified as being male and there is no evidence that the DNA sample itself was contaminated in any way."
For the full conviction review final report, click here:
If you'd like to listen to the 12-26-75 podcast, click here:
Tulare DA: Golden State Killer not suspect in Exeter teen's 1975 murder
GOLDEN STATE KILLER