The Zodiac Killer attacked at least eight people in California between 1966 and 1969. He claimed to have killed at least 37 people, although only five of those deaths can be definitively attributed to the killer. While the Zodiac Killer has never been caught, his case is still active, and now one major mystery has been solved: an international team of private citizens and codebreakers have cracked the Zodiac Killer’s mysterious “340 Cipher” 51 years after it landed on the FBI’s desk.
Zodiac had a habit of taunting police by sending letters to the press, and several of those contained intricate codes, some of which he claimed would ultimately reveal his identity. This marks the second coded message to be broken by civilians. In July of 1969, a puzzle sent in pieces to The San Francisco Chronicle, San Francisco Examiner, and Vallejo Times-Herald newspapers in 1969, was cracked by a school teacher from Salinas, Calif., and his wife. The puzzle was known as the 408 cipher after the number of characters it depicted. This first cipher laid out what was essentially the Zodiac Killer’s manifesto, with lines such as “I like killing because it is so much fun.”
This second cipher came to be known as the “340 Cipher,” and was sent in a letter to the San Francisco Chronicle in November of 1969.
“I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO CATCH ME,” reads the message, according to David Oranchak, a member of the team which deciphered the cryptogram. “THAT WASNT ME ON THE TV SHOW WHICH BRINGS UP A POINT ABOUT ME, I AM NOT AFRAID OF THE GAS CHAMBER, BECAUSE IT WILL SEND ME TO PARADICE ALL THE SOONER, BECAUSE I NOW HAVE ENOUGH SLAVES TO WORK FOR ME, WHERE EVERYONE ELSE HAS NOTHING WHEN THEY REACH PARADICE, SO THEY ARE AFRAID OF DEATH. I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW LIFE IS LIFE WILL BE AN EASY ONE IN PARADICE DEATH.”
The coded message contains 340 characters, but no obvious clues.
The section which says “That wasn’t me on the TV show” refers to an episode of a Bay Area television talk show, The Jim Dunbar Show, where attorney Melvin Belli was the guest. Someone claiming to be the Zodiac called the Oakland police station on Oct. 22, 1969, demanding Belli, or Boston attorney F. Lee Bailey, appear on the show. While the show was being broadcast, the station received several calls from a man who called himself “Sam” and kept hanging up in order to stop police from tracing the calls.
The cryptic message was sent two and a half weeks later. On Dec. 20, 1969, Belli received a letter from the Zodiac at his home. To confirm he was the killer, a portion of a victim’s bloodstained shirt was included in the envelope. The message was interpreted as the Zodiac Killer’s way of saying Sam was an imposter.
The coded message was first submitted to the FBI Laboratory on Nov. 13, 1969. Their Cryptographic and Racketeering Records Unit reviewed numerous proposed solutions over the past 51 years, but none had merit. On Friday, Oranchak posted a video on YouTube detailing how he, Sam Blake of Australia, and Jarl Van Eycke of Belgium cracked the code. “Last weekend, a team I’m on solved the 340 and submitted it to the FBI,” Oranchak told the San Francisco Chronicle. “They have confirmed the solution. No joke! This is the real deal.”
To break the cipher, the team collected information about variations in the cipher text.
“My main contribution here was actually enumerating many possible reading directions through the cipher, in total over 650,000,” Sam Blake told ZodiacKillerFacts.com. “David and I both ran these through azdecrypt and zkdecrypto respectively. Interestingly, only azdecrypt was able to find the fragments of the complete solution. It was a needle in a haystack. Even finding the right haystack to search in was lucky.”
The three experts checked and expanded each other’s work extensively before submitting their findings to the authorities on Friday, Dec. 4. The bureau called Oranchak three times on Saturday morning.
“When I talked to the FBI, they only needed to make one change to the solution.” Oranchak told ZodiacKillerFacts.com. The team deciphered a six-letter section as “soo her.” Oranchak said the FBI’s “cryptanalyst called me and she said she thinks it’s supposed to say, ‘sooner’ instead.”
The FBI confirmed the cryptologic researchers’ claims about the cipher popularly known as Z340. “The FBI is aware that a cipher attributed to the Zodiac Killer was recently solved by private citizens,” the FBI’s San Francisco office tweeted Friday. “The Zodiac Killer case remains an ongoing investigation for the FBI San Francisco and our local law enforcement partners. The Zodiac Killer terrorized multiple communities across Northern California, and even though decades have gone by, we continue to seek justice for the victims of these brutal crimes.”
While the Zodiac Killer was never caught, the most likely suspect remains Arthur Leigh Allen, who died of a heart attack in 1992 having never been formally charged with the killings. But other suspects have held the attention of amateur sleuths through the years, although only a small handful have appeared credible. Perhaps the cracking of the latest Zodiac code will finally bring investigators a step closer to solving the case.