Gareth Sewell Penn (born January 1st 1941) inadvertently or otherwise thrust himself into the Zodiac limelight when he set about University of California, Berkeley professor Michael O' Hare, convinced that this man was indeed the killer everybody had been searching for.
He was also convinced Michael O' Hare was involved in the murder of Joan Webster, a 25-year-old Harvard graduate who disappeared after her arrival at Boston's Logan International Airport on 28th November 1981. Her remains were subsequently discovered nearly nine years later in April 1990 in Hamilton, Massachusetts. Having thrust himself into the Zodiac search, he himself became the focus of much scrutiny, effectively having the tables turned back the other way, as he now became promulgated as the possible Zodiac killer.
Gareth Penn, a California writer with an interest in cryptography, was born in 1941, making him 27 years of age at the time of the Lake Herman Road murders on December 20th 1968.
He was of high intellect, having graduated in Germanic languages and Medieval Germanic languages from the University of California, Berkeley. He entered the army in 1965, becoming an expert marksman, before he left in 1971. His interest in the Zodiac case was influenced by his father, an army cryptographer during World War 2, who had extensive knowledge of coding.
Penn became obsessed with the Zodiac case and laid out his thoughts, evolving the Radian Theory in which the killer was orchestrating his murders based on specific coordinates on the map. This suggestion initially carried some merit in view of certain styles of Zodiac communication. The Phillips Road Map/Button letter and 'Bus Bomb' letter crosshairs, along with the phrase 'PS. The Mt. Diablo Code concerns Radians & # inches along the radians' at the foot of the 'Little List' letter were case in point.
Gareth Penn's radian theory for the Mount Diablo map discovered that once the arc was laid upon it, the extending lines passed over the Blue Rock Springs Park and Presidio Heights murder scenes, however, due to a grid positioning error, it actually fell nearer to a 60 degree angle, and therefore not a radian value.
But it was these theories, some believed were indicative of a man upset and annoyed that no one was clever enough to solve the clues the Zodiac Killer laid out for everyone, that he was giving a little nudge in the right direction without being overtly obvious - and thereby placing himself, Gareth Penn, under close scrutiny as a prime suspect in the killings.
Here is a phone interview with Gareth Sewell Penn by the Zodiac Killer Insight series in 2019, answering some questions put to him regarding the Zodiac murders. It is a brief but interesting exchange.
JOAN WEBSTER (19th August 1956-28th November 1981)
Joan Lucinda Webster, a 25-year-old Harvard graduate, disappeared after her arrival at Boston's Logan International Airport on 28th November 1981, and her remains were discovered nearly nine years later in April 1990 in Hamilton, Massachusetts.
The cause of her death remains undetermined and nobody has been charged with her supposed abduction and murder.
The case is constantly kept alive by determined individuals keen for a resolution to this thirty-two year old murder mystery. http://joanwebstermurder.yolasite.com/
"The decades since Penn fixed his sights on me have not been a living hell, much as that would spice up this story. They have been an ordinary life, punctuated by one or another flurry of fuss from Penn, sometimes involving pages of numbers (for example, the data pages from my PhD thesis) with this or that sequence picked out, circled, and "decoded" into words that fit somehow into Penn’s model of the crimes. I don't want to be cute about the murders, which not only left victims and grieving relatives in their wake, but also frightened a lot of people, and frustrated California and Massachusetts law enforcement. So, for the record: I am not the Zodiac killer, had absolutely nothing to do with those (or any other) murders. As far as I know, I wasn't even in California when any of them happened. Similarly, I had nothing to do with the death of Joan Webster, a Boston college student whose murder Penn has also tried to pin on me".
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