Content warning: This article contains a mention of sexual abuse and discussions of murder.

Earlier this month, the Case Breakers, a team of former law enforcement investigators, thought they uncovered the identity of the infamous serial killer who terrorized Northern California in the late 1960s.

In a press release, the group explained that new forensic and physical evidence led them to the identity of the Zodiac Killer. One photo of the Case Breakers’ purported killer featured similar forehead scars to a 1969 sketch of the Zodiac Killer. The team also believed that encrypted letters they’d been investigating had revealed the individual’s name: Gary Francis Poste.

For a moment, we all exhaled. We allowed ourselves to believe that the seemingly unremorseful menace was a man who’d died in 2018 at 80 years old. Some of us even found supposed screenshots of infamous online music reviews that have been attributed to Poste and shared a small chuckle. 

The celebration and laughter came crashing to a halt when the FBI refuted the supposed discovery of the Zodiac Killer’s identity. In a statement to CNN, The San Francisco Police Department confirmed the case remained an open investigation.

The Zodiac Killer gained notoriety by writing cryptic letters to law enforcement and local media. They taunted newspaper publications with ciphers and encrypted messages. To this day, police believe that the Zodiac Killer was responsible for at least five murders in the San Francisco Bay Area from 1968 to 1969. The killer self-reported up to 37 victims in their letters. 

The most recently solved code from the Zodiac Killer was decrypted in 2020. A team of experts cracked the code to a 1969 Zodiac cipher. The message, written in the form of symbols, read, “I hope you are having lots of fun in trying to catch me. I am not afraid of the gas chamber because it will send me to paradice [sic] all the sooner because I now have enough slaves to work for me.” It took experts 51 years to crack this message. 

Then there’s a long list of suspects who have been investigated since the murders. The only suspect named by authorities was Arthur Leigh Allen, a convicted child molester. Allen died of a heart attack in 1992, before prosecutors could gather enough evidence against him, and thus the state was never able to formally charge him. The evidence against Allen was entirely circumstantial. 

Mike Mageau — one of the Zodiac’s only two surviving victims — did positively identify Allen. Allen was also confirmed to be close to the location of some of the Zodiac Killer’s murders. A partial fingerprint from the Zodiac’s letter, however, was later tested and compared to Allen’s, and investigators did not find a match. Additionally, DNA evidence has suggested that Allen could not be the Zodiac Killer, and retired police handwriting expert Lloyd Cunningham, who worked extensively on the case, said that the Zodiac’s handwriting clearly did not match with Allen’s.

Though the Zodiac Killer’s notorious murders happened half a century ago, people still continue to send their tips to the police. To this day, the killer’s identity remains one of the biggest unsolved cases in North America.