Former Los Angeles prosecutor turned author Vincent Bugliosi -- who put Manson and his followers behind bars and penned "Helter Skelter," the best-selling account of the crimes -- told ABCNews.com last month that Atkins was the only one of the group that he might accept parole for.
Bugliosi said he was not an advocate for her release, but believes that Atkins' freedom would have meant little opportunity for her besides death outside a prison.
"They were all sentenced to death, and that would have been the proper punishment," he said of the Manson murderers. "All of them, except Susan Atkins ... should spend the rest of their lives behind bars. They should be very happy their lives were spared and not take it to the next level."