From the late 1960s to the early 1970s, the infamous Zodiac Killer haunted northern California, taunting authorities and the uneasy public with a series of coded letters and cards. He has five confirmed victims, though he boasted that he's killed 37. Next to the Victorian slaughters of Jack the Ripper, it's one of the most notorious unsolved cases in true crime.
But according to 38-year-old French-Moroccan engineer and business consultant Fayçal Ziraoui, we may finally have some answers.
Ziraoui was first turned onto the more than 50-year-old cold case when he came across an article in the French magazine L'Obs discussing how, to date, no one had ever cracked the Zodiac killer's two baffling ciphers. Though this particular case of code-cracking had stumped decades worth of cryptographers, law enforcement agents, and self-motivated sleuths (amateur or otherwise), half a century's worth of fruitless research wasn't going to discourage Ziraoui. Never one to adhere to limits or back down from a challenge, he set out to accomplish the impossible.
When Ziraoui allegedly cracked the code—a feat he says he accomplished a mere two weeks after beginning—by using creative techniques and an encryption key which came forward in December. Of the previously unsolved ciphers, one of them is believed by Ziraoui to reveal the killer's true identity. And with these discoveries, he immediately took to posting on the internet.
Since posting messages and videos across countless online forums dedicated to the case, Ziraoui has owned up to being a bit tactless in unleashing his findings to the world. Not only have the efforts of numerous like-minded sleuths been debunked over the years, but Ziraoui dove headfirst into a large yet tight-knit community which takes the investigation very seriously, laying down his findings as definitive truths. The online community was in an immediate uproar about his claims, with one moderator going so far as to remove one of Ziraoui's posts from a site.
But while some skepticism is to be expected, why were the keyboard sleuths of this community so furious? While some reasonably doubted the validity of Ziraoui's claims due to the speed with which he developed them, a more likely reason for the uproar is that the community has been debating for so long, they're not quite ready to give up the chase.
During the Zodiac killer's reign of terror in the Bay Area, he sent a total of four ciphers—a trademark of sorts. They contained a jumble of letters and symbols, messages that proved irresistible to media outlets as he sent them out. The first cipher was cracked fairly quickly after it was received, stating little of note besides the fact that the Zodiac killer loved murdering people. In December of 2020—as mentioned in the article that inspired Ziraoui—three cryptologists solved a second cipher using a code-breaking program, yet this message provided no more significant clues about the killer's identity.
The remaining two ciphers, known as Z32 and Z13, were long thought to be too short to be solved. But Ziraoui simply thought trying would be a fun task to occupy him during the coronavirus quarantine. However, he had the thought that perhaps the Zodiac killer used the same encryption key—the one the cryptologists released into the public domain after solving the second cipher—and it could be used for the remaining two.
He cracked the 32-character code first—the location of bomb that never went off, despite the authorities' failure to solve the message. In a process which naysayers have dismissed as convoluted, Ziraoui said he works through a half-dozen steps of letter-to-number substitutions and the use of a code-breaking program to transform the code into coherent words. It became an obsessive task. One that consumed him throughout the day and kept him up at night.
When Ziraoui's decoding of Z32 led to a location previously mentioned in another of the Zodiac killer's alleged postcard, he eagerly turned his efforts to Z13 to uncover the killer's identity. Going through the same process, the message is said to read, "My name is KAYR."
It didn't take long for Ziraoui to draw the connection between "KAYR" and the suspect Lawrence Kaye. In fact, Ziraoui thought that this supposed typo was very similar to others found in previous ciphers, and might be attributed to the killer's own human error. He didn't believe the accuracy of the information he decoded could be a coincidence.
But could this merely be a case of confirmation bias?
The leader of the team which cracked the second cipher in December, David Oranchak, doesn't believe Ziraoui's efforts can be proven true. However, David Naccache and Emmanuel Thomé—two French specialists in cryptography—stated that Ziraoui's discoveries should be considered by law enforcement, and his process was sound. The F.B.I. and the San Francisco Police Department have declined to comment thus far.