Story highlights Manson is being held in isolation after being caught with a weapon in October

"We will never hear from Charlie Manson again," says Debra Tate, sister of victim

"I have put five people in the grave. ... I'm a very dangerous man," Manson told psychologist

Manson, 77, serving a life sentence for nine murders, didn't show up to hearing

Notorious killer Charles Manson, 77, was denied parole Wednesday after a California parole panel "could find nothing good as far as suitability" for his being paroled, a commissioner said.

Manson didn't show up for his parole hearing, which was held at a state prison in Corcoran, California, where he is serving a life sentence.

Manson's next parole hearing was scheduled for 15 years from now, meaning he could die in prison.

California Board of Parole Hearings Commissioner John Peck said that Manson has accumulated 108 serious disciplinary violations in prison since 1971 and that he has shown no indication of remorse for his nine murder convictions.

Manson hasn't participated in any self-help programs or vocational training, Peck said. Manson also hasn't shown any parole plans, he said.

Peck also cited Manson's statement to a psychologist in a prison interview on November 2, 2011, in which Manson stated:

"I am special. I am not like the average inmate. I have put five people in the grave. I've been in prison most of my life. I'm a very dangerous man," Manson told the psychologist, according to a report read aloud by Peck during the hearing.

Those statements marked a change from Manson's past denials of having murdered nine people in 1969, and the statements showed some insight into his crimes, Peck said, reading from the report.

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But two-member parole panel still found the statements troubling, denying him parole and scheduling his next hearing for 15 years from now, the maximum allowed under law, Peck said.

That would put Manson at age 92 for his next hearing, unless he petitions the board for an earlier hearing.

Los Angeles County Deputy District Attorney Patrick Sequeira, who opposed Manson's parole at the hearing, said Manson is likely to die in prison. Sequeira said he didn't know which "five people" Manson was referring to in his statement to the psychologist.

"When you think a person will be 92 years old, it's very likely that there will be no further parole hearings for Mr. Manson," Sequeira told reporters after the 80-minute hearing concluded.

"He does not deserve to be returned to society," the prosecutor added. "He has a history of refusing to cooperate, not only with psychologists for evaluations, but also for treatment."

DeJon R. Lewis, Manson's state-appointed attorney, who has never met his client, said he didn't know why Manson didn't show up for the hearing. Manson hasn't appeared at any of his parole hearings during the past 15 years.

Manson didn't come out of his cell to participate in an interview with Lewis a month ago, Lewis told the parole panel.

"Quite frankly, I don't think he could have helped himself today by speaking on the record," Lewis told reporters after the hearing.

Manson now has been denied parole 12 times, authorities said.

Manson was initially sentenced to death for the grisly 1969 slayings of pregnant actress Sharon Tate and eight others by a group of his followers -- called his "family" -- as part of what prosecutors said was an attempt to incite an apocalyptic race war between whites and blacks during the country's massive social unrest.

Manson's death sentence was changed to life in prison after California's death penalty was overturned for a period during the 1970s.

Manson and his family staged crime scenes to appear as if African-Americans or the Black Panthers committed the murders, Sequeira told the panel. He called the stabbing and shooting deaths "domestic terror."

After the race war, Manson and his followers would emerge from their desert retreat "to rule the world," Sequeira told the panel. Manson and his followers believed the Beatles' "White Album" predicted such an apocalyptic war, Sequeira told the panel.

Debra Tate, the sister of Sharon Tate, who attended Wednesday's hearing, told the parole panel that she believed Manson declined to attend the proceeding because he didn't want to hear her or any other victim's impact statement.

"He clearly does not want to be released into the public," Tate told the parole board.

After Manson was denied parole, with his next hearing scheduled for 2027, Tate was "elated," she told reporters. She has been attending Manson's parole hearings for the past 15 years.

"I was very pleased that we will never hear from Charlie Manson again," Tate told reporters. "I don't have to see him again. For this one, it's over."

Last October, Manson was found to be in possession of an inmate-manufactured weapon and he is now being held for 15 months in isolation in a secured housing unit in the California State Prison Corcoran, said Commissioner Gilbert Robles, the other member of the two-person parole panel.

In another incident, Manson was also found to be in a possession of a cell phone, another prison violation, the panel said.

Of the 108 serious discipline violations committed by Manson in prison, 35 of them were violent, Sequeira said.

Seven of the serious disciplinary violations occurred since Manson's previous parole hearing in 2007, the prosecutor said.

Manson has a history of manipulative and controlling behavior and has a record of mental health issues, including schizophrenia and a paranoid delusional disorder, Robles said.

Manson also had a history of using drugs such as LSD, amphetamines and barbiturates, but he hasn't participated in any self-help programs for the last 11 years, Robles said.

Manson dropped out of school at 3rd grade when he was 9 years old, and he spent years in boy reformatories. But he hasn't used his prison time to obtain a GED, which is an alternative high school diploma, according to Robles and Peck.

Manson posted an IQ of 121 in 1972, which is average to high average of intellectual functioning, Sequeira said.