The ruling moves Van Houten, now 73, a step closer to release after more than five decades behind bars, although a potential legal battle remains as the state’s governor has previously blocked all efforts to free her.

Van Houten was 19 when she joined Manson’s “family,” an apocalyptic cult who hatched a bizarre plot to commit murders across Los Angeles in hopes of sparking a race war.

Manson, who notoriously led his gang to murder heavily pregnant actor Sharon Tate and her friends in a killing spree that shocked the nation, died in prison in 2017.

While Van Houten was not involved in those murders, she has admitted to participating in further killings by the group on the following night, during which she stabbed Rosemary La Bianca, a grocer’s wife, up to 16 times.

Van Houten has been recommended for parole five times since 2016, but California governors Jerry Brown and Gavin Newsom have vetoed on each occasion.

Newsom’s latest veto in 2022 argued that Van Houten could still be a danger to society, and said she had not fully explained how she fell under Manson’s sway and came to commit horrific acts of violence.

But appeal judges on Tuesday overturned Newsom’s veto, with a 2-1 majority finding that “there is no evidence to support the Governor’s conclusions” and ruling in favor of her release.

They noted Van Houten’s exemplary inmate behavior, and found that Newsom’s refusal to release her “fails to account for the decades of therapy, self-help programming, and reflection Van Houten has undergone in the past 50 years.”

The ruling does not guarantee Van Houten’s imminent release. Newsom can still ask for the case to be referred to California’s supreme court, in a process that could take years to resolve.

California prosecutors are expected to file a motion to stay Van Houten’s release on parole while those proceedings are ongoing.