Author Makes Case for Zodiac Killer’s Most Convincing Suspect in Decades

When it comes to the Zodiac Killer, there’s no shortage of crackpot theories and “my dead dad did it” books. It’s a case that, despite having far fewer victims than other notorious American serial killers, refuses to leave the public consciousness. This is exactly what the Zodiac Killer wanted: he thrived on the publicity he generated by sending cryptic notes and numbers throughout his killing spree. Five people in the Bay Area have been confirmed to have been murdered by the Zodiac between December 1968 and October 1969, although many Zodiac detectives believe his body count may be higher.

It’s a case that seems remarkably solvable. The Zodiac Killer left behind two survivors who both shared many memories of the attacks. There’s a DNA sample (though of questionable utility), bloody fingerprints found at a crime scene in San Francisco, and the many letters sent by the killer himself. It’s this paper trail that has led to feverish speculation as amateur sleuths dig into obscure pop culture references and language ticks.

Those clues led Kobek to Doerr, a Bay Area man who was a member of both Mensa and the militant conservative group the Minutemen. LAmag details Kobek’s investigationwho found:

— Doerr was an active zine writer, and some of his work touched on themes found in the letters of the zodiac. More interestingly, Doerr once wrote about how to make a bomb out of ammonium nitrate and fertilizer. Zodiac did the same, and both instances contained the same error.
– According to Doerr’s daughter, Gloria, her father had a history of violent behavior and physical abuse against family members. The article claims that three Zodiac Killer attacks – on Lake Herman Road, Blue Rock Springs Park and Lake Berryessa – took place at “teen hangouts” that “Gloria herself frequented”.
– Kobek relates the cross-shaped symbol that Zodiac used to sign its letters to the target symbol sometimes used by the Minutemen.
– Doerr worked at the Mare Island shipyard in Vallejo and served in World War II and the Korean War. It was long assumed that the Zodiac Killer was affiliated with the military.

The details were compelling enough that Gloria Doerr was apparently swayed; the article says she reluctantly agreed with Kobek that there were signs that her father was a candidate for the Zodiac Killer. Paul Doer died in 2007 at the age of 80.

The case is of course only circumstantial. No hard evidence connects Doerr – or anyone else – to the Zodiac Killer murders. Several previous suspects were matched against fingerprints on file, but no match was found.

The San Francisco Police Department is keeping a case open on the Zodiac Killer.