Who was the Zodiac Killer in The Truth About Jim? Culprit's fate explored

As per the makers of the true-crime documentary, The Truth About Jim, Jim Mordecai could have been the Zodiac Killer of the 1970s. The Max documentary was released on February 15, 2024, with its four episodes dropping simultaneously. Mordecai was Sierra Barter’s step-grandfather, whom she suspects of being the culprit for 7 to 10 murders in the San Francisco Bay area.

Mordecai, who died of cancer at the age of 67 in 2008, was not under suspicion at the time of the start of the investigation. However, after Sierra opened the case, the basic investigation into his involvement started. The Santa Rosa Hitchhiker’s case is still open with multiple suspects.

The HBO Max docuseries speculates whether Mordecai went around by the name Zodiac Killer and was responsible for the serial murders.

Disclaimer: This article contains spoilers and advises the reader’s discretion.

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The Truth About Jim: Who is the Zodiac Killer in the docuseries?

Images of Jim Mordecai in The Truth About Jim (Image via HBO Max)

The docuseries, The Truth About Jim explores whether Jim Mordecai was the infamous Zodiac Killer. Evidence proves coincidental, as the Zodiac Killer operated in the late 1960s and early 1970s in the area around Santa Rosa. Since Jim also resided in the same San Francisco Bay area, the operative zones coincide.

Some of the unusual evidence found in his home after his death included mismatched ornaments worn by teenage girls during the 1970s. While Judy, Jim’s third wife, Shannon, her daughter, and Sierra’s mother disposed of the trinkets before they could be analyzed, they spoke about them.

Moreover, the sketch of the Zodiac Killer shared at the time had some similarities with Jim. However, despite having uncanny similarities with the Zodiac Killer, expert Mike Butterfield overrules the possibility of Jim Mordecai being the Zodiac Killer. As such, Jim may have been influenced by the killer in his modus operandi.

While hardly any information is available about the Zodiac Killer, Jim was a well-remembered San Francisco Bay resident. Known to be a high school agriculture teacher and a landscape designer, Jim is remembered to be an abusive family member. Moreover, he boasted of having assaulted his colleagues and female students.

Some of his children have alleged, in the documentary The Truth About Jim, that he r*ped them or attempted to do so. Jim was never suspected in his lifetime. He married three times and led a life that he considered normal, albeit abusive. He died of cancer in 2008 at the age of 67.

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Who were the other suspects in the Santa Rosa Hitchhikers murders?

File picture of Jim with his children (Image via Max)

HBO Max's The Truth About Jim talks about Sierra Barter’s step-grandfather being involved in a series of murders based on the personal experiences of family members and members of society.

While it is still under speculation whether Jim Mordecai or the Zodiac Killer were responsible for the Santa Rosa murders and whether they were the same person, the open case has many more suspects.

One of the suspects was Fredric Manalli, a creative writing instructor at Santa Rosa Junior College. After his accidental death in August 1976, a disturbing sadomasochist drawing of Kim Wendy Allen, one of the victims, was retrieved from his belongings.

The Sonoma County detectives have many suspects in the open case. (Image via Max)

Jack Bokin, a criminal convicted of violent rapes and assaults, was considered a suspect by the Sonoma County detectives since the Santa Rosa murder victims were s*xually assaulted. While there are some similarities between the condition of some of the victims and Bokin’s modus operandi, DNA testing has not been done.

However, the most likely suspect for the Sonoma County authorities has been Arthur Leigh Allen, who has been under suspicion since 1971 until the present. The former elementary school teacher served for two years, charged with child molestation.

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What is the documentary, The Truth About Jim, about?

The Truth About Jim tries to uncover the true identity of Jim Mordecai as a serial murderer, the Zodiac Killer, based on the available evidence more than a decade after his death. While the show uncovers various chilling details about Jim, who was both abusive and frightening, the evidence is not conclusive.

Jim’s step-granddaughter, Sierra, claims to have felt something eerily strange about him, particularly when her mother Shannon disliked him. Reaching out to all members of Jim’s extended family helped Sierra put the story together.

While Jim may have had brutal secrets in the past, Sierra’s insistence on trying to tie him up as the Zodiac Killer or with the Santa Rosa murders, despite the authorities not confirming it, makes the docuseries farfetched.

The Truth About Jim is produced and directed by Skye Borgman. Premiered on Max on February 15, 2024, the docuseries is currently available for streaming on the platform.