Van Houten's attorney told a three-judge panel of the 2nd District Court of Appeal that his client is remorseful and takes responsibility for her crimes. A state prosecutor said the 69-year-old has placed too much blame on Manson.
Van Houten was 19 when she and fellow members of Manson's cult fatally stabbed Los Angeles grocer Leno LaBianca and his wife, Rosemary, in 1969. The killings took place a day after other so-called Manson family members killed actress Sharon Tate and four others in crimes that shocked the world.
Van Houten, who is serving a life sentence, was not involved in the other killings.
A parole board has recommended that Van Houten be released three times since 2016, finding that she's no longer a threat to society. Former Gov. Jerry Brown blocked the first two recommendations, and the third is heading to Gov. Gavin Newsom.
Separately from Newsom's decision, the appeals court is reviewing a lower judge's order that blocked Van Houten's release last year.
The parallel matters had the judges wondering whether they still would have jurisdiction to rule if Newsom denies Van Houten parole.
Her attorney, Rich Pfeiffer, told them they have a duty to issue a ruling, adding that no elected politician will ever agree to Van Houten's parole because of the infamy of the case.
"If the courts don't release Miss Van Houten, she's never going to be released," Pfeiffer said. "The courts are empowered to make difficult decisions, and sometimes unpopular decisions, to be able to enforce the law. That's what courts are there for. Otherwise it turns into mob rule."
Deputy Attorney General Jill VanderBorght said the issue should rest with whatever Newsom decides. She said Pfeiffer's argument that Van Houten is unlikely to get released without a court decision was irrelevant.
"We're only looking at this single instance of parole reversal," she said. "We don't have to think of tomorrow or ever or politics. In fact, the court should not."
The judges gave Pfeiffer and VanderBorght five days to file arguments on the issue of jurisdiction. The judges have three months to decide on Van Houten's parole.
Courts in general can be reluctant to interfere in parole matters, said Samuel Pillsbury, a criminal law professor at Loyola Marymount University in Los Angeles.
"It is highly emotional," Pillsbury said. "The voters have decided the governor should have a veto on this, so the courts would prefer to let this process play out."
If the decision comes down to the governor, Pillsbury said Van Houten has an uphill battle.
"The Manson case is one of a kind," he said. "The entire state and much of the nation still feel some degree of trauma from that, and it makes it a very different kind of case from an elected official's point of view."
Sharon Tate's sister, Debra Tate, was at the hearing and told The Associated Press that Van Houten doesn't deserve to be released under any circumstances and hasn't personally apologized to the victims' families.
"A truly remorseful individual would reach out in any way they could to say they're sorry, not to the people who have the power to free them, but to the people they've hurt the most," Tate said.
Former inmate Cheryl Minichilli said after the hearing that she's never seen anyone more remorseful than Van Houten.
"She showed me what it took to look deep inside and figure out what I did ... wrong so that I could repair me," said Minichilli, adding that Van Houten mentored her and dozens of other inmates over the years.
"Her whole life is dedicated to helping other people," she said.
In denying Van Houten parole last year, Los Angeles Superior Court Judge William Ryan found that she would "pose an unreasonable risk of danger to society," citing the brutal nature of the crimes.
During one of her parole hearings, Van Houten said she was traveling up and down the California coast when acquaintances led her to Manson. She candidly described how she joined several other members of the group in killing the LaBiancas, carving up Leno LaBianca's body and smearing the couple's blood on the walls.
Manson died of natural causes in 2017 at a California hospital while serving a life sentence.
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