California Gov. Jerry Brown denied parole Friday for Leslie Van Houten, the youngest follower of murderous cult leader Charles Manson who is serving a life sentence for killing a wealthy grocer and his wife more than 40 years ago.

Brown overturned the recommendation of a parole board that found Van Houten was no-longer the violent young woman who committed a gruesome murder and was now fit for release. She has completed college degrees and been a model inmate.

Image: Leslie Van Houten is seen during a hearing before the California Board of Parole Hearings
Former Charles Manson follower Leslie Van Houten is seen during a hearing before the California Board of Parole Hearings at the California Institution for Women in Chino, Calif., Thursday, April 14, 2016. Nick Ut / AP
The Democratic governor acknowledged her success in prison and her youth at the time of the murders, but he wrote in his decision that she failed to explain how she transformed from an upstanding teen to a killer.

"Both her role in these extraordinarily brutal crimes and her inability to explain her willing participation in such horrific violence cannot be overlooked and lead me to believe she remains an unacceptable risk to society if released," Brown wrote.

Van Houten, 66, participated in the killings of Leno La Bianca and his wife, Rosemary, a day after other so-called "Manson family" members murdered pregnant actress Sharon Tate and four others in 1969. Van Houten did not participate in the Tate killings. The crimes and the trials that followed fascinated the world and became tabloid fodder.

"Gov. Brown has done a good thing here, and I think he sees what we see — that this was an unrepentant killer," said Lou Smaldino, nephew of the La Biancas.

At 19, Van Houten was the youngest Manson follower to take part in the killings after she joined the cult in the 1960s.

The murders were the start of what Manson believed was a coming race war that he dubbed "Helter Skelter" after a Beatles song. Manson had his followers prepare to fight and learn to can food so they could go underground and live in a hole in the desert, Van Houten told the parole board.

Van Houten's lawyer, Rich Pfeiffer, said he expected Brown's decision because of the political pressure put upon him. He said he will challenge the decision in Los Angeles County Superior Court, where he hopes Van Houten's parole will fare better "because the judges and the courts have less political pressure than does someone like the governor."

Van Houten's next parole hearing could come in as little as a year, Pfeiffer said.

At her parole hearing, Van Houten described how she helped secure a pillow over the head of Rosemary La Bianca with a lamp cord and held her down while another member of the Manson family began stabbing the woman in her home.