On the night of October 11, 1969, 24-year-old husband, student and cab driver Paul Stine was murdered in the upscale Presidio Heights neighborhood in northern San Francisco. The killer took the cab keys, the driver’s wallet and a large portion of Stine’s shirt. A letter sent to The San Francisco Chronicle two days later claimed responsibility for the murder and provided a piece of Stine’s bloodstained shirt as proof. Two other pieces of the shirt were sent with two other Zodiac communications in November and December 1969. The unique communications demonstrated a direct link between the killer and the writer of the letters, and these envelopes and letters were obvious candidates for potential DNA testing which could reveal the Zodiac’s genetic profile.
Efforts to obtain DNA from these communications began in the late 1990s, and a report documenting the testing for the SFPD crime lab noted the results. “Few cells” were recovered from the envelope which contained the first piece of Stine’s shirt and the letter taking credit for the crime. The second envelope, sent on November 9, 1969, was apparently not tested or the results were not included in the report. The third envelope, mailed to attorney Melvin Belli on December 20, 1969, was tested and “few cells” were recovered.
Paul Stine’s shirt became a vital piece of evidence linking the killer to the letters and established a chain of evidence which could help identify the Zodiac. The killer sent three pieces but a larger portion of the shirt remained missing, an indication that the killer retained that part of the shirt, perhaps in order to relive his crimes or to include more pieces in further communications in order to prove his connection to the crime.
A pair of mens gloves were found in the back seat of Paul Stine’s cab on the night of the murder. Photographs of evidence on display in the offices of the San Francisco Police Department appear to show these gloves stored in a plastic bag. A report prepared and distributed by the California Department of Justice stated that the gloves found in the cab were men’s gloves, size seven. Men’s gloves are sized using two different methods. One method measures the size of the hand in inches while the other method creates an estimate based on height and hand size. According to either method, a size seven glove is small or extra small.
Pam Hofsass worked for the San Francisco Police lab from 1989 to 2015. Hofsass then became the director of the Forensic Services Division for Contra Costa County. In an interview for the History Channel documentary series The Hunt for the Zodiac Killer, Hofsass talked about the evidence examined for possible DNA leads. “I started looking at some of the evidence from the Paul Stine shooting,” Hofsass explained. “And lo and behold, there was a pair of bloody gloves that were found in the, at the scene. We didn’t know who the gloves belong to or what the connection is. Those gloves appeared to be moldy, there was some blood on the outside of the gloves. The glove DNA report confirmed that it’s Paul Stine’s blood on the outside, and then there’s an unknown male profile on the inside.”
The gloves had been a source of confusion for many years due to conflicting accounts regarding their value as evidence. In his 1986 book Zodiac, former San Francisco Chronicle cartoonist Robert Graysmith described the police investigation of the Stine murder scene and wrote, “Just under the dash, Toschi found a pair of dull-black leather gloves. They were soaked with blood but were too small for a man. Later he discovered that they belonged to a woman passenger from earlier in the day.” Photographs and film prove that the gloves remained in the custody of the SFPD. Pam Hofsass clearly stated that the gloves were still in SFPD custody years after Graysmith’s 1986 book claimed that the gloves belonged to a female owner identified by SFPD Inspector David Toschi. In the updated edition of Zodiac Unmasked, Graysmith wrote that the gloves were important evidence belonging to the killer. His description of a scene from the film based on his book features this puzzling passage regarding the police search of a trailer owned by suspect Arthur Leigh Allen. “The trailer search continues as the inspectors find two windbreakers. ‘Hey, hey,’ says Toschi, ‘black gloves. Size seven, same as we found in the cab. He’s got the same shoe size and glove size as Zodiac – I’m sure it’s just a coincidence.’” If Toschi had determined, in 1969, that the gloves belonged to a woman passenger, as Graysmith wrote, he would have no reason to believe that the gloves belonged to the killer when searching Allen’s trailer in 1971. If Toschi knew that the size seven gloves were too small to belong to the killer or Allen, Toschi would not have any reason to say that Allen had the same gloves size as the Zodiac. Allen was more than six feet tall, weighed more than 200 pounds, and he had large hands. The discovery of the gloves is curiously absent from Graysmith’s other accounts of the trailer search in both Zodiac and Zodiac Unmasked, although such distortions regarding the gloves, the search, and Allen do appear in the film adaptation.
In 2002, San Francisco police cooperated with the production of the ABC television documentary Primetime. SFPD Inspector Kelly Carroll appeared in on-camera segments displaying Paul Stine’s shirt. According to some unconfirmed accounts, investigators attempted to obtain fingerprints and possible DNA evidence from the shirt based on the belief that the killer had handled the shirt while moving the victim and tearing away the large shirt piece for use with later letters. “Touch DNA” technology enables investigators to obtain DNA from trace amounts of genetic material left behind after touching some objects. While the procedure is a popular crime-fighting technique in television shows such as CSI and Criminal Minds, the process of obtaining “Touch DNA” is difficult especially when examining aging evidence.
A reddish/brown hair was found underneath a stamp but the material was insufficient for DNA testing. The hair color reflected the statements by eyewitnesses who saw the killer walking away from the scene of the Stine murder and provided this description: “White Male Adult, in his early forties, 5’8″, heavy build, reddish-blond ‘crew cut’ hair, wearing eyeglasses, dark brown trousers, dark (navy blue or black) ‘Parka’ jacket, dark shoes.” This description was subsequently adjusted for the SFPD composite sketch which published this description: WMA 35-45 years old, 5’8″ Reddish brown hair, Crewcut, Heavy Rim Glasses, Navy blue or black jacket.
Dr. Cyndi Holt of the San Francisco police DNA lab examined the Zodiac envelopes and stamps, and she stated that a partial genetic profile was obtained from a stamp, reportedly from an envelope sent on November 8, 1969. The partial genetic profile could be used to exclude suspects but was not sufficient to conclusively identify any individual as the Zodiac. According to unconfirmed reports, the DNA profile was obtained from DNA recovered from the front of the stamp instead of the back of the stamp. Critics claimed that this process indicates that the DNA taken from the front of the stamp may not belong to the killer and therefore cannot be considered a valid “Zodiac” DNA profile. Despite the alleged questions about this DNA evidence, the partial genetic profile was used by SFPD to exclude various suspects, including the “prime suspect” investigated by Vallejo police, Arthur Leigh Allen. Other information indicated that other DNA evidence recovered from Zodiac envelopes/stamps did not match Allen.
Speculation and debate about the DNA evidence and its potential to identify and exclude suspects continues, but the facts and common sense favor the simplest scenarios. Absent credible evidence to conclude otherwise, the most logical scenario was that the Zodiac purchased and handled paper, stamps, and envelopes used in his communications, that he handled each sheet of paper several times as he wrote, examined, folded, and placed the paper into the envelopes, that he handled the envelopes in this process and licked the envelope flaps, that he handled and then licked the stamps before placing them onto the envelopes and applying pressure with his fingers, that he also handled the envelopes while writing the names and addresses, and that he further handled the envelopes as he transported and then mailed the envelopes. This behavior was perfectly consistent with the behavior of any person writing and mailing letters at that time, and the killer likely left DNA on the letters, stamps, envelopes. The possibility exists that a postal worker left DNA on the Zodiac communications during brief and limited contact with the items but the most logical explanation was that DNA was most likely left by the killer as he handled the items over an extended period of time. Claims that DNA found on suspected Zodiac communications must be contaminated or unreliable do not constitute credible evidence or good reason to assume that the DNA does not belong to the Zodiac.
DNA may prove to be the most crucial evidence in the decades-long hunt for the Zodiac killer, and the debate surrounding the search for “Zodiac DNA” will most likely continue until the killer is finally identified.