Prior to, and continuing on after the Lake Berryessa attack on September 27th 1969, investigators painted the Zodiac Killer as a sexual deviant, targeting couples (primarily the females), because of some relationship inadequacies in his own life. Despite no evidence whatsoever that the Zodiac murders were sexually motivated, the psychological profile of the killer was deemed sexual in nature. The next murder was the clinical, execution style shooting of a lone male taxicab driver in the heart of San Francisco on October 11th 1969.
The attribution of a sexual component to the Zodiac crimes were not scotched by the taxicab murder however. The Zodiac Killer was now being labeled a "latent homosexual" in a Paul Avery article on October 18th 1969.
The next murder in San Francisco with the Zodiac pseudonym placed at the crime scene (similar to Berryessa), was the murder of a gay man, Robert Michael Salem on April 15th 1970, who had been callously stabbed numerous times in his 745 Stevenson Street apartment - and "Zodiac" had been written in the victim's blood on the apartment wall.
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