The August 10,1969, Zodiac 408 cipher key by " concerned citizen"

The suspected Zodiac "13 hole card" sent Oct 5, 1970, was created on a 3x5 index card

Ca. 14 month prior, August 10,1969, a Zodiac 408 cipher key was sent to Vallejo Police Department.
The cipher key was accompanied by a short typewritten note , ALSO written on a 3x5 index card expressing hope that "the enclosed key will prove beneficial to you in connection with the cipher letter writer." It was signed " concerned citizen."

IMO a fact that support the theorie that the cipher card was sent by the Zodiac killer.




Info on the August 10,1969, a Zodiac 408 cipher key:
A little-known letter containing a key to the cryptogram was sent anonymously to the Vallejo Police on August 10, one day after the Harden solution was made public. It was postmarked San Francisco, and the typewritten address was to a VPD sergeant.

The key was handwritten on a sheet of white paper, and was accompanied by a short typewritten note on a 3x5 index card expressing hope that "the enclosed key will prove beneficial to you in connection with the cipher letter writer." It was signed " concerned citizen." The key was described in an FBI report as "generally valid" and "substantially accurate", but this is unsurprising since the author probably read the decryption in the newspaper and simply made his own key letter by letter. One useful palmprint was found on the envelope, but it was never matched to any individual.

Good point Foreigner, I agree

Theforeigner wrote:

Info on the August 10,1969, a Zodiac 408 cipher key:
A little-known letter containing a key to the cryptogram was sent anonymously to the Vallejo Police on August 10, one day after the Harden solution was made public. It was postmarked San Francisco, and the typewritten address was to a VPD sergeant.

The "concerned citizen" signature is odd but I also have to wonder if this couldn't have merely been sent by someone who had read about the solution in the newspaper to inform Vallejo P.D. of the solution and spelling out how it was encoded. It could have been sent by Zodiac by I'm not sure why he would have felt the need to send a key AFTER the 408 cipher had been solved. It would be interesting to see the actual correspondence.

entropy wrote:

Theforeigner wrote:

Info on the August 10,1969, a Zodiac 408 cipher key:
A little-known letter containing a key to the cryptogram was sent anonymously to the Vallejo Police on August 10, one day after the Harden solution was made public. It was postmarked San Francisco, and the typewritten address was to a VPD sergeant.

The "concerned citizen" signature is odd but I also have to wonder if this couldn't have merely been sent by someone who had read about the solution in the newspaper to inform Vallejo P.D. of the solution and spelling out how it was encoded. It could have been sent by Zodiac by I'm not sure why he would have felt the need to send a key AFTER the 408 cipher had been solved. It would be interesting to see the actual correspondence.

But if this was sent by Zodiac, he probably did it when the Harden Key had NOT yet been published. This was mailed the day the Harden solution was published, so it seems likely Zodiac could have wrote this when no solution was published. He might have dropped it in the mail, only to see that day or the next day the Harden solution in the newspaper.

There's a conversation about the use of "citizen" around here somewhere which I've lost.
Here's the refence to the FBI report.
http://www.zodiackillerfacts.com/gallery/displayimage.php?pid=1104&fullsize=1

smithy wrote:

There's a conversation about the use of "citizen" around here somewhere which I've lost.

It recently came up with Nin's observation of Thomas Dougerhty's use of the word.

https://zodiackillersite.forummotion.com/t1368p30-thomas-dougherty-s-code-theory#35463