Nearly five decades after the Zodiac Killer began his 1960s murder spree in Northern California, his identity remains unknown. But History Channel's new docuseries, The Hunt for the Zodiac Killer, examines a man the show's team believes could be a suspect — someone who's name has been circulated in online forums for years, but has rarely been covered by the mainstream press. So, just who is Ross Sullivan?
A quick Google search turns up dozens of blogs speculating about Sullivan's alleged involvement, but any official information about him is sparse. He doesn't appear to have ever been charged in connection to the case, and if he was ever questioned by authorities, those details don't seem to be readily available (though since the Zodiac murders are still technically an open investigation, it's unlikely that information would be made public).
According to the History Channel's website, Sullivan was a student at Riverside City College during the 1966 murder of Cheri Jo Bates in Riverside, California — a killing that bore many similarities to those committed by the Zodiac. As detailed in The Hunt for the Zodiac Killer, Bates' killer stalked her, disabled her car, used a knife as a weapon, and left military boot prints at the crime scene, all details in line with the Zodiac's M.O.
Afterward, The Press-Enterprise, then called The Daily Enterprise, received a typed letter titled “The Confession.” It described aspects of Bates' murder not yet released to the public, just as the Zodiac later taunted media with letters regarding his San Francisco victims. As noted by the History series' investigators, the first Zodiac message was not received until 1969 — three years after Bates' death — so it's not possible that her killer could have been a Zodiac copycat. Analysts for the show also found linguistic matches between the Zodiac's letters and those sent by Bates' killer: Both referred to murder as a "game," misspelled twitch as "twich," and used the word "squirm." Furthermore, the letter from Bates' murderer was signed with a "Z." If Bates was one Zodiac's victims, it would mean his killings expanded 400 miles South and two years earlier than originally thought, and finding Bates' murderer could potentially hold the key to uncovering Zodiac's identity. At that point, he possibly wasn't an experienced killer, which could have made him more prone to slipping up and leaving behind crucial evidence.
The Riverside Police Department has kept the name of their prime suspect in Bates' murder under wraps, and did not immediately return Bustle's request for comment. But midway through The Hunt for the Zodiac Killer's premiere, the investigation turns to Sullivan. While at Riverside City College, he worked at the library where Bates was last seen, and after her death, employees reported that he disappeared for several days. A current staff member interviewed for the show described him as a quiet, unsocial man who made her feel uneasy, and said that fellow employees had openly wondered if he was a suspect in Bates' case. She added that Sullivan almost always wore an army jacket and military-style boots — much like the footprints found at both Bates' murder scene and Zodiac's Lake Berryessa stabbings — but that when he returned to work, he was wearing an entirely new set of clothes.
Though eye witness accounts are notoriously unreliable, Sullivan also matched the Zodiac's rough description — somewhere around six feet, about 200 pounds, stocky build — and based on the photo displayed in the show, he bares an uncanny resemblance to the Zodiac's composite sketch. Also according to the show, as an English student, Sullivan reportedly took classes on cryptology — something the Zodiac Killer made infamous use of in his coded taunts. And finally, he reportedly moved to Northern California in 1967, just before the officially recognized Zodiac murders began.
Per the History channel's website, Sullivan was hospitalized several times for bipolar disorder and schizophrenia. His current whereabouts appear to be unknown, though according to the series, he was born in 1941, which would make him about 76 if he's still living. Most of the blogs speculating about Sullivan claim that he died in 1977, per a Find a Grave entry for a Ross M. Sullivan who lived in Santa Cruz, California.
Over the years, police have investigated hundreds of subjects, and if there are substantial links between Sullivan and Zodiac, it's likely a lead they've chased. Without hard evidence, it's impossible to make any definitive connections, but The Hunt for the Zodiac Killer investigators clearly intend to continue their search in the episodes to come.