Although I believe the Cheri Jo Bates murder and accompanying communications have nothing to do with the Zodiac Killer, it would be foolish to unequivocally rule out of any of the commonly mentioned pre-canonical crimes suggested as possibly being the work of the Bay Area killer. So let us once again examine the Halloween card on October 27th 1970, that inspired Phil Sins to contact American journalist, Paul Avery, shortly after its arrival at the San Francisco Chronicle, and point out his thoughts on the relationship between the Halloween card and the murder of Cheri Jo Bates on October 30th 1966. Even though a link between the Zodiac murders and Riverside had been considered the previous year by investigators, this wasn't common knowledge on October 27th 1970. Phil Sins was also unaware that three letters had been mailed to the Riverside Press Enterprise, Riverside Police Department and Joseph Bates on April 30th 1967 by somebody claiming to be the killer of Cheri Jo Bates.
In 2012, Mike Morford of Zodiac Killer Net interviewed Phil Sins, who stated that despite going to the Riverside Police Department with Paul Avery "where the letters & desktop were discussed or shown", he himself did not get to see them. Therefore, he had no knowledge regarding the contents of the Bates' letters when he drew his original conclusions between the Zodiac and Riverside cases. And neither, have we yet proved, did the Zodiac Killer. This is why the Halloween card and the Zodiac Killer's previous letter, the Little List letter mailed on July 26th 1970, are so curious. If not responsible for any of the Riverside activity, the Zodiac Killer could have been aware of the Cheri Jo Bates case and the Confession letter when he mailed both the Little List letter and Halloween card, because the Inside Detective magazine published on January, 1969 featured both. However, he wouldn't have been aware of the three Bates' letters (had he not been the author).
In 2012, Mike Morford of Zodiac Killer Net interviewed Phil Sins, who stated that despite going to the Riverside Police Department with Paul Avery "where the letters & desktop were discussed or shown", he himself did not get to see them. Therefore, he had no knowledge regarding the contents of the Bates' letters when he drew his original conclusions between the Zodiac and Riverside cases. And neither, have we yet proved, did the Zodiac Killer. This is why the Halloween card and the Zodiac Killer's previous letter, the Little List letter mailed on July 26th 1970, are so curious. If not responsible for any of the Riverside activity, the Zodiac Killer could have been aware of the Cheri Jo Bates case and the Confession letter when he mailed both the Little List letter and Halloween card, because the Inside Detective magazine published on January, 1969 featured both. However, he wouldn't have been aware of the three Bates' letters (had he not been the author).
Paul Avery Had the Zodiac Killer read the Inside Detective magazine and thought now is the time to plant the seed in investigators minds that he may have been responsible for the Riverside murder? The Confession letter mailed on November 29th 1966 read "She died hard. She squirmed and shook as I chocked her, and her lips twiched. She let out a scream once and I kicked her in the head to shut her up". The Little List letter on July 26th 1970 read "Some I shall tie over ant hills and watch them scream + twich and sqwirm". Did the Zodiac Killer deliberately group this sequence of words together (including the misspelling of twich) to encourage individuals to draw the comparison between both communications and force investigators to strongly consider his involvement in the Riverside murder (and authorship of the Confession letter)? Or were these word comparisons sheer coincidence? Before you draw any conclusions, it is important to consider the Halloween card, which followed three months later.
The whole premise of the Halloween card cover was seemingly chosen on the understanding that when the card was opened it would reveal his name. One notable feature of the card was the prominence of the word "By", followed by the four methods of death. The Zodiac Killer had written "By Fire, By Gun, By Rope and By Knife". The 1966 Confession letter also tempted us with a name, when the author began his typewritten letters with "The Confession", followed by the word "By" and several underscores. The word "By" playing a significant role in both communications. We also have the Halloween theme running through the 1970 card and the Riverside murder of Cheri Jo Bates, whose lifeless body was discovered on Halloween morning. But it's the addition of the "Z" symbol (meant to infer "Zodiac") placed at the foot of the Halloween card that conjures the most interest. The Zodiac Killer had mailed 15 confirmed communications prior to October 27th 1970 (probably in excess of 20), yet he had never once used the letter "Z" to sign off a communication. In fact, no communication subsequent to October 27th 1970, verified or otherwise, ever signed off with the letter "Z".
The whole premise of the Halloween card cover was seemingly chosen on the understanding that when the card was opened it would reveal his name. One notable feature of the card was the prominence of the word "By", followed by the four methods of death. The Zodiac Killer had written "By Fire, By Gun, By Rope and By Knife". The 1966 Confession letter also tempted us with a name, when the author began his typewritten letters with "The Confession", followed by the word "By" and several underscores. The word "By" playing a significant role in both communications. We also have the Halloween theme running through the 1970 card and the Riverside murder of Cheri Jo Bates, whose lifeless body was discovered on Halloween morning. But it's the addition of the "Z" symbol (meant to infer "Zodiac") placed at the foot of the Halloween card that conjures the most interest. The Zodiac Killer had mailed 15 confirmed communications prior to October 27th 1970 (probably in excess of 20), yet he had never once used the letter "Z" to sign off a communication. In fact, no communication subsequent to October 27th 1970, verified or otherwise, ever signed off with the letter "Z".
San Francisco Chronicle headline on November 12th 1969 The only time the Zodiac Killer used the letter "Z" as a signature, was in conjunction with Halloween on October 27th 1970. This is what is so interesting about the potential "Z" like signatures accompanying the April 30th 1967 Bates' letters, concerning the murder and discovery of Cheri Jo Bates' body on Halloween morning. Letters that the Zodiac Killer would have had no knowledge of on October 27th 1970, unless he was the unlikely author of these three communications. Of course, the signatures on the Bates' letters may not have been the letter "Z", and the "Z" signature on the Halloween card may just have been a fortunate coincidence, but these three letters would have been unknown to Phil Sins when he contacted Paul Avery about a Zodiac connection. So, I suppose the discovery of the Bates' letters was an added bonus to Paul Avery when he entered the Riverside Police Department in 1970, and ultimately made the "Z" connection between the cases. Was it extremely fortunate for the Zodiac Killer to tie together Halloween, the prominent wording of "by" and the perceived "Z" signature - in combination with the common phraseology between the Little List letter and Confession letter, just three months previously - or did the Zodiac Killer have inside information through law enforcement and/or the newspapers, thereby enabling him to create the seed in the mind of investigators - or was he involved in the murder and/or letter writing in Riverside four years earlier?
The Zodiac Killer may have done exactly the same thing on November 8th 1969 when he claimed seven victims within the Dripping Pen card, forcing investigators to draw the conclusion he was responsible for the murder of Kathie Snoozy and Debra Furlong in San Jose on August 3rd 1969 by the addition of "Aug" in his chronological list of months. As he did on March 22nd 1971, mailing us another cryptic card, this time encouraging investigators to connect him to the Donna Lass disappearance on September 6th 1970 by the addition of "Lake Tahoe areas" and "Sought Victim 12". Once Paul Avery had connected the Riverside and Zodiac murders together, the Zodiac Killer then cemented that notion by giving "credit for stumbling across his Riverside activity". However, not once did he ever categorically claim or prove these murders were his. He only let investigators draw such a conclusion.
The Zodiac Killer may have done exactly the same thing on November 8th 1969 when he claimed seven victims within the Dripping Pen card, forcing investigators to draw the conclusion he was responsible for the murder of Kathie Snoozy and Debra Furlong in San Jose on August 3rd 1969 by the addition of "Aug" in his chronological list of months. As he did on March 22nd 1971, mailing us another cryptic card, this time encouraging investigators to connect him to the Donna Lass disappearance on September 6th 1970 by the addition of "Lake Tahoe areas" and "Sought Victim 12". Once Paul Avery had connected the Riverside and Zodiac murders together, the Zodiac Killer then cemented that notion by giving "credit for stumbling across his Riverside activity". However, not once did he ever categorically claim or prove these murders were his. He only let investigators draw such a conclusion.