Now, author Tom O'Neill is sharing never-before-heard recordings from his prison phone interview with Manson while researching his new book "Chaos: Charles Manson, the CIA and the Secret History of the Sixties."
O'Neill told Inside Edition he was trying to learn who else might have been involved in the Manson Family slayings.
But Manson kept mum.
“Hell, no, I’m not gonna give you no name,” Manson told the author.
“Can you give me a hint? Can you tell me where to look?” O'Neill asked.
“No way, I’m not an informant, I’m not a snitch,” Manson told him.
O'Neill told Inside Edition that Manson prided himself on keeping cult secrets — secrets he took to the grave when he died in 2017.
“He never told anything about the murders ... he kept all the information to himself," said O'Neill. "He didn't want to be a rat, that was the lowest form of human being."
O'Neill added that he thinks the Manson Family may have taken more lives than the nine known.