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arthur leigh allen zodiac suspect

Arthur Leigh Allen has the dubious honour of being the most infamous suspect in the Zodiac Killer case. The main reasoning behind this is that he was the named suspect in a best-selling book on the murders which was then the basis of a hit movie. The problem, as is the case with most books, movies or documentaries in which the killer is seemingly revealed, is that pieces of information are habitually neglected if they do not fit the narrative been sought.

Despite the ommissions, the book Zodiac, written by Robert Graysmith, does make a compelling case against Arthur Leigh Allen. He was also certainly a suspect in the eyes of the police. In fact, he is the only suspect to have been served with a search warrant for his home.

However, a lot of the damming evidence provided in the book (and movie) are vastly exaggerated (and some argue even completely made up). More importantly, several facts that point to Arthur Leigh Allen’s innocence rather than guilt are also glossed over or ignored entirely.

Initial Suspicion

Arthur Leigh Allen initially became a suspect in 1971 after an estranged friend of his named Don Cheney told police he suspected Allen. Cheney stated that Allen had told him he fantasized about committing a series of murders and sending letters to the police. According to Cheney, this occurred sometime between 1967 and 1969 while the two were still friends.

Arthur Leigh Allen was thirty-five-years-old at the time of the murders of David Faraday and Betty Loe Jensen in 1968, the first known zodiac victims. In that same year, he had lost his job when he faced accusations of molesting a child at the school. Several years later he would serve time due to a similar charge.

Handwriting And Fingerprints

The police took the accusations of Don Cheney seriously and investigated Arthur Leigh Allen closer. Detectives had his handwriting checked against letters from the Zodiac Killer. The conclusion of the handwriting expert stated there was no match with that of letters the Zodiac Killer had sent to the police and various newspapers.

Fingerprints also exonerated him. Arthur Leigh Allen’s prints were not a match to any prints taken from various crime scenes, including those found in the cab of final known victim Paul Stine. Prints taken from various letters, including a palm print, also failed to be a match.

The Watch

zodaic brand watch

Despite this, in September 1972, after further communications with Don Cheney, police searched the home of Arthur Leigh Allen. Again no actual evidence against him was found, though some circumstantial evidence was unearthed. One piece of “evidence” that is invariably cited by those who suspect Arthur Leigh Allen is a Zodiac brand watch. This was located inside the property and has become an interesting pointer against Allen as its brand logo was virtually identical to the one used in letters sent by the killer.

The one problem is that the watch was nowhere near as rare as Graysmith would have you believe in his book. Although it is a nice bit of circumstantial evidence it isn’t the holy grail it is seldom made out to be.

Following the search, Arthur Leigh Allen took part in a polygraph test. Allen passed. With fingerprints, handwriting and now a polygraph test all going in his favour it would seem Arthur Leigh Allen wasn’t the man police were looking for. He also looked nothing like any of the composite sketches given by witnesses. Other than his wearing size 10 and a half boots, the same size as boot prints found at Lake Berryessa, and a bunch of circumstantial evidence the case against Allen seemed weak.

Arthur Leigh Allen – Convicted Child Molester

Arthur Leigh Allen was far from a good person. He had a particular fondness for children. On September 27, 1974, after years of allegations regarding his like of children Allen was arrested for molesting a young boy. On March 14, 1975, he was found guilty and sent to Atascadero State Hospital. He was released on August 31, 1977.

This leads to more circumstantial evidence against Arthur Leigh Allen, and probably the most compelling, as the Zodiac letters stopped in 1974. Even more compellingly they possibly began again in 1978 after Allen’s release, though these are considered to be hoaxes by most authorities in the case. It is also worth noting there was a gap in the letters between 1971 and 1974 too for which Arthur Leigh Allen was not incarcerated.

Arthur Leigh Allen’s interest in children also brings us to why Don Cheney may have had a reason to make up accusations about him. The two had fallen out in 1968 as Cheney told Arthur Leigh Allen’s brother that Allen had attempted to molest his young daughter. Researchers who distrust Cheney as a witness and Allen as a suspect often assume this was Cheney’s way of attaining revenge on Allen.


In 1991 Arthur Leigh Allen was again looked into after Don Cheney embellished his story (no one seemed to notice this was after the release of Graysmiths book and he used information from within it). For the first time, Arthur Leigh Allen’s name became public knowledge (Graysmith had given him an alias as Bob Hall Starr so as to not get sued).

Whilst still under investigation Arthur Leigh Allen was found dead in his home. He died due to complications of diabetic kidney failure. Once more no evidence was found against Allen to suggest he was the Zodiac Killer.

More letters written by Allen, found in the search, were checked but again the handwriting failed to match that of letters sent by the Zodiac Killer. Despite handwriting, fingerprints, composite sketches and a polygraph test all pointing away from Arthur Leigh Allen he is still by many considered to be the killer.

The Identification

zodiac killer wanted poster

Several witnesses failed to identify Allen or conclusively stated he wasn’t the man responsible. That is except one man…Michael Mageau, a survivor of the Blue Rock Springs attack.

It wasn’t until 1991 that Michael Mageau identified Arthur Leigh Allen as the man who shot him back in 1969. Pretty damming evidence on the face of it. However, questions were raised.

At the time of the attack in 1969, Mageau said the assailant shined a bright light into his face and he only got a brief glimpse at the attacker. From this description, he stated the man was around 5’8, Allen was 6’0 to 6’1. The attacker was heavyset but in Mageau’s words “real beefy” not ” blubbery fat” and around 200lbs, Allen was around 250lbs in 1969 and didn’t match the description of beefy. Finally, Mageau stated he had light brown, almost blonde, short curly hair, Allen had brown hair and was balding.

Unsurprisingly given the discrepancies and that 22 years had passed, Vallejo PD deemed the identification of Arthur Leigh Allen as unreliable.


In 1996 it was reported a hair was recovered from under the stamp of a Zodiac letter sent after the murder of Paul Stine. The sample, discovered by Dr Cynde Holt at the San Francisco DNA lab, could only provide Mitochondrial DNA, in other words, it couldn’t identify the killer, as Nuclear DNA would, but it could clear a suspect. In 2002 the DNA sample did just that as after it was compared to that of Arthur Leigh Allen the test came back negative. It seemed Arthur Leigh Allen had been officially cleared.

In more recent years the reliability of the test has been questioned with a debate over how good a sample the stamp was. Some have stated that the DNA sample was actually obtained from above the stamp, and so could come from anyone and not necessarily.

One of the more bizarre theories by those who suggest Allen is the Zodiac is that he had someone else lick his stamps for him to cover his tracks (some even suggest he had an accomplice to write the letters). Covering your DNA trail may happen nowadays but back then in the ’70s no one had any idea that DNA testing would come so far so the idea that Arthur Leigh Allen would cover his tracks in such a way seems exceedingly far fetched.

Which letter the sample was taken from has also been a matter for debate, with some researchers believing it came from one of the letters believed to be a hoax. Of course, all these doubts are raised by those who believe Arthur Leigh Allen is a suspect. You have to ask would the same doubts be raised if the DNA had been a match by these same people.

Further Reading And Sources




The Case Of The Zodiac Killer