Was Arthur Leigh Allen the Zodiac Killer? Theories and suspects

Now, a new Netflix docuseries, titled This Is the Zodiac Speaking, is revisiting the case, focusing on evidence about Arthur Leigh Allen, the only person police have ever officially named as a suspect for the murders.

The documentary centres on the Seawater family, who viewed Allen as a father figure through their childhood.

This Is the Zodiac Speaking also features never-before-seen evidence and interviews from those who knew the killer, as well as archival footage and interviews with Allen before his death.

So, who was Arthur Leigh Allen and why did the Seawater family believe he was the Zodiac Killer?

With the documentary now available to watch on Netflix, read on for everything you need to know.

Who is the Zodiac Killer?

The Zodiac Killer is one of the most infamous unsolved serial killer cases, with no one ever convicted.

The Zodiac Killer murdered at least five people from 1968 to 1969 and wrote several messages in code and riddles, demanding they were published on the front page of newspapers in San Francisco.

Who was Arthur Leigh Allen?

Allen remains the only suspect who has been officially named in the Zodiac Killer investigation.

While not much is known about Arthur Leigh Allen's early life, he joined the US Navy in 1951 before being honourably discharged in 1959.

Allen studied at California Polytechnic University and graduated in 1960 and from there, went on to become an elementary school teacher.

In 1962, Allen was fired from Travis Elementary School for having a firearm on school grounds.

He then became a teacher in 1966 at Valley Springs Elementary School before he was fired and subsequently arrested for child molestation.

According to Time magazine, he spent three years in prison and served five years of felony probation until 1982.

Was Arthur Leigh Allen the Zodiac Killer?

Arthur Leigh Allen has been the only publicly identified suspect by the police, however there was never enough evidence to charge him.

Therefore, it cannot be confirmed whether or not Arthur Leigh Allen was the Zodiac Killer.

In the documentary, the Seawater siblings claimed that Allen confessed to being the Zodiac killer.

According to David and Connie Seawater, Allen would take them on weekend trips away or visits to the cinema, and it was during a sailing trip with Allen in 1991 that Connie claims she asked him if he was the Zodiac killer, to which he said that if he told her, he would have to kill her.

"I thought it was a big joke," Connie says in the documentary.

David Seawater claimed he got a full confession from Allen, who told him he was the Zodiac killer when his health was declining.

When David and Connie's mother Phyllis died in 2017, they found a box with letters between Phyllis and Allen, where he spoke about the Zodiac.

"Every time someone mentioned police to me, I'd jump," Allen wrote in a letter show in the Netflix series.

"Seeing a murder headline would turn my palms sweaty," another read, while a more revealing one read: "The most dangerous thing is when I almost decided to confess."

Other theories that sleuths have about Allen is that during the three years Allen was in prison, the murders and letters from the Zodiac killer stopped.

Allen was also identified by survivor Michael Mageau in a police line-up.

However, police were unable to charge Allen due to a conflicting witness testimony.

Where is Arthur Leigh Allen now?

Arthur Leigh Allen died in 1992.

According to an autopsy report, he died from arteriosclerotic heart disease.

Who were the Zodiac Killer suspects?

While Netflix’s This Is the Zodiac Killer raises Arthur Leigh Allen as the likeliest suspect, nine other men have also been connected to the murders.

The other suspects are as follows:

• Lawrence Kane, who was selected out of a photo line-up by a woman who claimed she was abducted by the Zodiac.
• Ross Sullivan, a library assistant at Riverside City College, who bore a clear resemblance to the killer’s police sketch.
• Richard Gaikowski, who was named as the top suspect by Tom Voigt, a leading expert on the Zodiac killer who, along with other researchers, claimed Gaikowski matched sketches of the Zodiac.
• Gary Francis Poste, who was accused of being the killer in 2021 by a volunteer investigative group The Case Breakers, who claimed to have forensic evidence including DNA.
• Earl Van Best Jr, who was accused of being the Zodiac killer by his own son Gary Stewart and daughter-in-law Susan Mustafa. They noted a striking resemblance between Van Best and the police sketch of the murderer, as well as a partial DNA and print match.
• Louis Joseph Myers, who emerged as a suspect after his friend Randy Kenney claimed he confessed to the murders while dying of cirrhosis in 2001.
• Paul Doerr, who was named as a suspect in Jarrett Kobek’s 2022 book How to Find Zodiac.
• Richard Marshall, who became a suspect primarily thanks to his presence in Riverside, California, during the murder of Cheri Jo Bates in 1966.
• Jack Tarrance, who emerged as a suspect after his stepson, Dennis Kaufman, alleged that he was the infamous killer.

This Is the Zodiac Speaking is available to stream on Netflix now. Sign up for Netflix from £4.99 a month. Netflix is also available on Sky Glass and Virgin Media Stream.

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