The Zodiac Killer
In the absence of any other promising leads, however, San Francisco and Vallejo police saw Allen as the most viable of their Zodiac suspects. On September 14, 1972, a search warrant for his Santa Rosa property was issued, and detectives were soon combing through his trailer and cars looking for firearms, ammunition, clothing, and any other evidence that could link him to the crimes or letters. Nothing of the sort was found. 1 Major case prints - inked impressions of the entire hand, fingertip to palm - were taken, as were samples of his left- and right-handed writing. All were tested by state experts against the Zodiac evidence. In no case was there a match. California handwriting analysts even went so far as to state that Allen's writing "definitely was not that of the Zodiac killer". 2 He was given a polygraph test and passed it.
The matter seemed resolved until 1986, when author Robert Graysmith leveled his pen at Allen in his groundbreaking case study, ZODIAC. Once a best seller and now in its 29th printing, ZODIAC has been cited as a source by almost every subsequent work on the case. Graysmith was tipped to Allen's suspect status by local authorities, and carried on an unofficial investigation of him in the early 1980s without significant findings. Nonetheless, Allen remained the favorite of San Francisco detectives, and Graysmith followed suit, exaggerating the marginal links between Allen and the Zodiac case and mixing rumor with fact to convince the reading public that there was no doubt as to the killer's identity. The world knew him as "Robert Hall Starr," but to anyone who had met him, there could be no mistaking Allen.
In December 1990, when Ralph Spinelli was arrested for armed robbery in Lake Tahoe, NV, his bid for leniency included a tip to the Zodiac's identity: none other than Arthur Leigh Allen. Facing 30 years in prison, Spinelli claimed that Allen had told him in 1969 that he was going to San Francisco to kill a cabdriver. Perhaps not coincidentally, Allen's only arrest before his child molestation charge was for a fight with Spinelli. Under pressure following the success of Graysmith's book, and with the knowledge that Allen's Vallejo property had not been searched in 1972, VPD took advantage of Spinelli's negligible tip and searched Allen's Fresno Street basement. Seized were bomb-making materials, newspaper clippings, several firearms, a knife, a typewriter, and Allen's Zodiac watch. Of these, the knife and one handgun could have been Zodiac evidence (it is widely believed that the Zodiac was not responsible for the murder of Cheri Jo Bates or the typewritten confession that followed it), but neither led to charges or an arrest, and it can be assumed that they were unrelated. Allen's prints were submitted to the FBI Laboratory, and again the comparison came back negative. According to one newspaper report, "Allen was dismissed as a suspect". 3