This letter, mailed to the San Francisco Chronicle newspaper is similar to the Vallejo Times-Herald and San Francisco Examiner letters and contained Part 3 of a trinity of ciphers, which totaled up to become known as the 408 cipher, due to each part containing 136 characters.
The letters claimed credit for the first two attacks at Lake Herman Road on December 20th 1968 and Blue Rock Springs Park on July 4th 1969.
Betty Lou Jensen and David Faraday died in the December Lake Herman Road attacks, but in the following encounter with the Zodiac Killer at Blue Rock Springs, Michael Mageau survived despite being shot four times, however, his companion Darlene Ferrin was not so fortunate and succumbed to her injuries upon arrival at Kaiser Hospital at 12:38 am.
On August 8th 1969, just over a week after the arrival of the three letters, the 408 cipher was cracked by Donald Gene and Bettye June Harden of Salinas, California, who both used homophonic substitution to identify a solution.
The decoded cipher turned out to be the killer's thoughts and ramblings, containing numerous spelling errors either by design or otherwise, yet despite the Zodiac Killer claiming he would reveal his identity within the cipher it turned out he was not so forthcoming. However, it is significant that this communication to the San Francisco Chronicle newspaper differed from the other two July 31st letters, in that the Zodiac Killer specifically stated "in this cipher is my idenity". This section of cipher contained the 18 unsolved characters at its foot. When decoded using the cipher key applied to the rest of the cipher, it contained nothing more than gibberish. The unresolved part of the message read ebeorietemethhpiti.
The San Francisco Chronicle letter was also the only communication to begin with "This is the murderer", as opposed to "I am the killer" which began the Examiner and Vallejo Times-Herald letters.
The Zodiac Killer's communications to the San Francisco Chronicle, San Francisco Examiner and Vallejo Times-Herald exemplified this knowledge of a Target Backcloth perfectly, when he only threatened to kill couples in his address to the Vallejo Times-Herald (or stray people). He knew exactly where to find them, despite the fact it was highly unlikely he would continue to kill in the same area again. The Zodiac Killer never used the word couples in his address to the San Francisco Chronicle and Examiner, suggesting that his knowledge of the Target Backcloth was less comprehensive and more uncertain in this city- and why at San Francisco he would target a lone taxicab driver rather than target the location, as he did at Lake Herman Road and Blue Rock Springs. As Kim Rossmo stated "The San Francisco murder differs significantly from the Zodiac's other crimes. Up to this point he was hunting in locations that had a good probability of containing his desired victims. Target selection was a function of area, not of an individual. However, it is unlikely the Zodiac was successful in all his searches; serial killers typically engage in extensive hunting activities, and for every attack there are many unsuccessful search attempts. In San Francisco, however, the Zodiac controlled the situation through his selection of victim type. The need for such control could be indicative of the distance the Zodiac had to travel to the crime site. Criminals who travel longer distances to offend are less likely to use uncertain target selection techniques". Read more.
Vallejo Times Letter and Part 1 of Cipher
San Francisco Examiner and Part 2 of Cipher
I like killing people because it is so much fun. It is more fun than killing wild game in the forrest because man is the most dangerous animal of all. To kill something gives me the most thrilling experence. It is even better than getting your rocks off with a girl. The best part of it is that when I die I will be reborn in paradice and all the (people) I have killed will become my slaves. I will not give you my name because you will try to slow down or stop my collecting of slaves for my afterlife. ebeorietemethhpiti
THE 18 UNSOLVED CHARACTERS [PT1]
THE 18 UNSOLVED CHARACTERS [PT2]
THE 18 UNSOLVED CHARACTERS [PT3]
THE 18 UNSOLVED CHARACTERS [PT4]
This is the murderer of the 2 teenagers last Christmass at Lake Herman + the girl on the 4th of July near the golf course in Vallejo
To prove I killed them I shall state some facts which only I + the police know.
1 Brand name of ammo Super X
2 10 shots were fired
3 the boy was on his back with his feet to the car
4 the girl was on her right side feet to the west.
1 girl was wearing paterned slacks
2 The boy was also shot in the knee.
3 Brand name of ammo was western
Here is part of a cipher the other 2 parts of this cipher are being mailed to the editors of the Vallejo Times and SF Examiner. I want you to print this cipher on the front page of your paper. In this cipher is my idenity. If you do not print this cipher by the afternoon of Fry.1st of Aug 69, I will go on a kill ram-Page Fry. night. I will cruse around all weekend killing lone people in the night then move on to kill again, until I end up with a dozen people over the weekend.