The Marilyn Tapes
But in a newly released audiotape, Engelberg downplays any past attempts by Marilyn to take her own life.
Asked if he was aware of other suicide attempts Marilyn may have made prior to her death, Engelberg told the investigator, "I'm not aware of any deliberate suicide attempt. I was only aware of the one time when she currently had too much to drink and had taken possibly slightly more than she should have. But that was not a serious attempt."
Carroll, in his re-examination, insists that the autopsy performed in 1962 by Dr. Thomas Noguchi of the Los Angeles County Coroner's Office was thorough. In fact, he had the full report reviewed by a renowned outside expert.
"He looked over the documents and he told us that this was a very competent and professional job considering the state of science at the time in 1962," says Carroll.
But Noguchi himself wanted to investigate further.
Not too long after Noguchi's initial examination, he decided he wanted to take a second look at the tissue samples but they went missing.
Asked what happened to those samples, Carroll says, "I don't know. I didn't at the time and I don't now think it was a sinister cover-up or destruction of evidence.
"The conspiracy theorists say there's evidence of a cover-up," Van Sant said.
"Yeah, I think that's fertile grounds for people to say, 'Oh boy, we got it now. We have a smoking gun,'" Carroll replied. "And my experience of the loss of material like that it's unfortunately pretty common."
Carroll was determined to confront one of the major conspiracy theories of the day; a man who identified himself as Rick Stone claimed he was an ambulance attendant called to Marilyn's house. He says he watched a doctor inject something into the dying movie star.
"And he opened that up [a doctor's bag] and took out a hypodermic syringe that was already filled and injected it into her heart," Stone said.
However, Carroll says Noguchi looked all over Marilyn's body for needle marks - but found none.
"He put a needle in her heart. I guarantee it. I was looking right at it," Stone insisted during the taped interview.
Carroll dismissed Stone's account as false and investigators also talked with Ken Hunter, who is believed to have been on the scene that night.
Asked about the story that a doctor plunged a needle into the area of Marilyn's heart and thereafter pronounced her dead, Hunter told Carroll, "That's b***s***."
Carroll found Hunter to be credible and what he says sheds light on the most elusive part of the mystery.
Hunter told Carroll he saw Marilyn lying on her side. Did she really die in that position? The first officer who arrived at the house shortly after 4:30 a.m. told the BBC that he believed the body had been positioned and the scene manipulated.
"No it was not a suicide. Marilyn Monroe was murdered and there's no question about it," Sgt. Clemmons, the watch commander that night, told the BBC.
But Carroll dismisses Clemmons' comments. "Yes, his opinion was not based on any kind of personal, professional training or experience. He was not a detective. He was not an experienced detective and certainly not a homicide detective."
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