Marilyn Monroe conspiracy theories explained after coroner makes bombshell claim about death

It's been 63 years since Marilyn Monroe, arguably one of the most famous people of all time, passed away at the age of 36.

So why is the cause of her death still so heavily debated?

On 4 August 1962, the actor - famous for her 'blonde bombshell' image - was found unconscious in her Los Angeles home by housekeeper Eunice Murray.

The Some Like It Hot star was discovered face down on her bed, her hand clutching a telephone receiver and numerous medicine bottles nearby.

Monroe's death would be officially ruled as a 'probable suicide' from an overdose of barbiturate drugs.

However, not everyone believes this is the case, with numerous conspiracy theories suggesting the actor - real name Norma Jeane Mortensen - died as a result of supposed foul play.

The death of Marilyn Monroe continues to split opinion (Bettmann/Getty Images)

Was Marilyn Monroe assassinated on the orders of the Kennedy brothers?

One of the most famous and most enduring theories about Monroe suggests that she was killed due to her alleged romantic links with both President John F. Kennedy and his brother Robert F. Kennedy.

This theory can be traced back to a pamphlet titled The Strange Death of Marilyn Monroe by Frank A. Capell, which alleges Monroe's death was linked to an attempt to cover up her rumoured affair with Robert Kennedy.

Capell also chucked in arguments about the whole thing being a 'communist conspiracy', which was pretty standard for the time.

Meanwhile, former detective and author Mike Rothmiller claimed in his 2021 book, The Night Bobby Kennedy Killed Marilyn Monroe, that the actor had left a note suggesting the president's brother was even supposedly planning to walk away from his marriage for her.

Former President John F. Kennedy and his brother Robert were linked to Monroe's death after being rumoured to have had affairs with her (Bettmann/Getty Images)

These theories would be regurgitated in further biographies, such as Norman Mailer's Marilyn: A Biography (1973), Matthew Smith's Victim: The Secret Tapes of Marilyn Monroe (2003) and Anthony Summers's Goddess: The Secret Lives of Marilyn Monroe (1985).

According to Summers's account of Monroe's final months, her addiction to barbiturates had been 'enabled' by Robert Kennedy after the actor threatened to expose their alleged affair.

However, he would ultimately conclude that while the circumstances around Monroe's death may have been covered up, he didn't believe she was deliberately killed.

Was Marilyn Monroe murdered by the mafia?

Her links to the Kennedy brothers aren't the theories swirling around the 'Marilyn Monroe was murdered' camp either, with connections between her and mob boss Sam Giancana also being used to suggest possible foul play.

In 1982, Milo Speriglio published Marilyn Monroe: Murder Cover-Up, in which he claimed that Giancana and union leader Jimmy Hoffa had killed her.

Numerous conspiracy theories, from aliens to presidents and mob bosses, have been linked to the actor's death (Baron/Hulton Archive/Getty Images)

Did Marilyn Monroe's body 'go missing' after her death?

The cause of Monroe's death isn't the only point of contention amongst fans of the Seven Year Itch actor, with speculation suggesting her body went missing also doing the rounds.

According to an article from Woman and Home, rumours that Monroe's body 'disappeared' for a number of hours between being discovered and arriving at the morgue crop up every now and again; however, there has never been any proven evidence to support this.

What are the new claims made by coroner Thomas Noguchi?

Coroner Thomas Noguchi was responsible for conducting the autopsy on Marilyn Monroe, with his experience being detailed in the book LA Coroner by Anne Soon Choi.

After conducting the autopsy, Noguchi collected samples of Monroe's blood, urine, liver, kidneys, her stomach and its contents to conduct a toxicology report.

However, head toxicologist Raymond Abernathy later concluded it was pointless to run further tests after discovering fatal levels of pentobarbital and chloral hydrate in her system.

However Monroe's death remains a probable suicide (Bettmann/Getty Images)

The conclusion sent 'alarm bells' ringing for Noguchi, with Choi writing: "A wave of anxiety washed over [Noguchi]. He knew that not running the additional tests would become a problem for him.

"It left too many questions unanswered, and ultimately, as the pathologist who conducted the physical autopsy, he would be held responsible."

He was, however, unable to challenge the decision, and samples taken from Monroe's body were later disposed of.

"Without a complete analysis, it was impossible to rule out that Monroe had died by injection rather than by swallowing pills." Choi added.

"But what could he do? He couldn't challenge Curphey or the head toxicologist."

Despite the lingering conspiracy theories, the cause of Marilyn Monroe's death has not changed from suicide, with a 1982 'threshold investigation' into her death finding no evidence to reopen the case as a criminal one.

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