Season 5 · Episode 33
Was Ross Sullivan the Zodiac Killer? The Riverside Connection Explained
18 March 2026·23:52
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Show Notes
Ross Sullivan remains one of the most debated and mysterious suspects in the Zodiac Killer case. In this episode, we explore the evidence linking Sullivan to both the infamous Zodiac murders and the earlier 1966 killing of Cheri Jo Bates at Riverside City College.
Sullivan, a library assistant at RCC, was present on campus at the time of Bates’ murder and later drew suspicion from co-workers who described him as unsettling and potentially dangerous. His sudden disappearance following the killing, combined with a change in appearance, raised further questions.
We break down the key elements of the case:
The Cheri Jo Bates murder and its possible connection to Zodiac
Witness accounts and co-worker suspicions
The disturbing “desktop poem” and its alleged link to Zodiac writings
Sullivan’s interest in cryptography and handwriting disguise
Physical similarities to the Zodiac composite sketch
The controversial Mikado connection
Conflicting alibi claims and institutionalisation records
But the case against Sullivan is far from airtight. We also examine the major weaknesses:
A significant height discrepancy with eyewitness descriptions
Fingerprints that reportedly did not match crime scene evidence
Claims of hospitalisation during key Zodiac attacks
The lack of formal investigation by law enforcement
Expert Review: Simon & Tom Analyse the Evidence
Former investigators Simon and Tom provide a critical breakdown of the Sullivan theory, questioning whether modern researchers may now have a broader view of the case than original investigators ever did.
They raise important questions about Sullivan’s mental health history, including what may have triggered his diagnoses and whether this is relevant to assessing his potential for violence.
The discussion challenges a common assumption: that Sullivan’s cremation prevents DNA analysis. Tom explains how familial DNA could still be used to eliminate or potentially link him through relatives.
However, both experts stress a key limitation—existing Zodiac DNA samples may not be reliable enough for definitive identification, meaning DNA may be more useful for elimination than confirmation.
They also highlight the importance of forensic integrity, noting that any evidence must have a clear chain of custody to stand up in court.
The height discrepancy is debated, with Simon viewing it as a major issue, while Tom argues eyewitness estimates—especially at night—are often unreliable.
Crucially, Tom warns against “linking assumptions”—building a case on the idea that Bates is a Zodiac victim, then linking Sullivan to Bates, which compounds uncertainty.
Both agree that much of the suspicion around Sullivan originates from co-workers rather than law enforcement, raising questions about how seriously he was ever investigated.
The conclusion: Sullivan is an intriguing suspect with some compelling overlaps—but the case remains circumstantial and far from proven.
With no confirmed DNA and conflicting evidence, the question remains open: was Ross Sullivan a viable suspect overlooked by police—or another compelling but ultimately flawed theory?
In the next episode, we turn to another major Zodiac suspect: Lawrence Kane.
About Crime Time Inc.
Season 5 of Crime Time Inc. broadens its reach across two sides of the Atlantic.
This season features cases from Scotland and across the wider UK — rooted in real investigative experience — alongside deep dives into some of the most infamous murder cases in American history.
Hosted by former detectives Simon and Tom, with experience in both the UK and the United States, including time working alongside the FBI, the show strips away sensationalism to explain how crime and justice really work.
Two crime worlds. One podcast.
New episodes released regularly throughout the season.
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