In reports previously published in these pages on the subject of the Zodiac murders, I have stressed the cryptographic side of the problem. The Zodiac claimed that he was identifying himself in some kind of code, the solution of which has eluded the police for over sixteen years. I believe that I have demonstrated to sufficiency that what he was using was nothing more complicated than Morse Code, written as binary numbers and expressed with a dazzling array of means, from angular measurement to the numbers of letters on a page (e.g., the very first Zodiac letter, titled The Confession, which rambles on and on without saying anything worth knowing, is written in 1623 letters; 1623 in binary is 11001010111, identical in form with the Morse MIKE O).
In "Te Moriarty Salutamus" (THE ECPHORIZER, November 1982), I alluded to documentary evidence that supports the identification of the murderer which I have made on the basis of cryptographic analysis of the Zodiac literature. I would like to touch on that evidence tangentially, because it illustrates the point that not just such esoterica as base-two arithmetic are beyond the grasp of the constabulary, but even such commonplaces as the calendar.
Students of the Zodiac have long been intrigued by the sporadic nature of his activity. The Riverside period, which comprises one murder and three documents, lasted six months. Between the last Riverside document months elapsed. Then followed a string of sixteen events (four attacks and twelve mailings.) This chain of events ended on 22 March 1971, when the [San Francisco] Chronicle received a postcard on which the murderer had pasted an architect's rendering of a condominium development at Lake Tahoe. This postcard was followed by almost three years of inactivity, after which the Zodiac returned for a six-month epilogue in 1974, which consisted of four letters to the Chronicle. Two-thirds of all the Zodiac events take place in the second period, which began with the double murder at Lake Herman Road on 20 December 1968 and ended with the Lake Tahoe Card in early 1971.
Even within that period, however, events were sporadic. In some instances, only days separated two events. In others, months went by without any activity on the part of the murderer. Many Zodiac theories have been based on interpretations of the sporadic nature of Zodiac events. There have been attempts to link the Zodiac chronology with phases of the moon, troop movements, even the stock market. Astonishingly, the most obvious connection is the only one which has, heretofore, never received any attention at all. Yet it is clearly the long-sought lowest common denominator.
Here is a timetable showing the dates of all the Zodiac events between 1968 and 1971. I have grouped together the five pairs (and in one instance, a triplet) of events which are separated by the shortest periods of time.
The pair labeled "A" takes place immediately before Boise Cascade Corporation filed a building permit application with the Regional Planning Commission in Reno for construction of a condominium project called Incline Village Unit 6 at Lake Tahoe. The project is the same one shown on the Zodiac's postcard of 22 March 1971. The group of events labeled "B" takes place immediately prior to the first meeting of the RPC at which its voting members took up Boise Cascade's application - and denied its permit. "C" immediately follows the second meeting at which the RPC considered, and denied, a construction permit for Unit 6. "D" precedes by a week the third and last time the RPC took up the matter of Unit 6, killing the project for ever and all time. That leaves "E", a week-long period, which concludes with a picture of Unit 6, and which presents one of the most intriguing aspects of the chronological problem.
In a two-part article published on 16 and 17 November, 1970, the Chronicle revealed that the murderer known in the Bay Area as "the Zodiac" had also murdered a young woman named Cheri Jo Bates in Riverside in late 1966. Although the Riverside murder is now firmly ensconced in Zodiac lore, the identity of the two murderers had never been established before. The identification had been made on the basis of handwriting evidence. It was a major Zodiac story, the first one which did more than either simply report what the murderer had done or indulge in idle speculation. The Zodiac gave plenty of evidence that he followed his press notices, responding specifically to accounts of his activities in the press, often to correct them. But he did not respond to the Riverside revelation until 15 March 1971, four months after the story appeared in the Chronicle. That response was followed a week later by a picture of Unit 6, then three years of silence. In the interim, the police poked around in the snowdrifts of Incline Village, Nevada, looking for a fresh corpse. They never found one.
It does not require a hyperactive fantasy to suppose that the picture of Unit 6 was part of the Zodiac's scheme of self-identification, the charade which he acted out on the front page of the Chronicle and whose solution meant the gas chamber for him. Flurries of activity on his part coincide with major administrative activity at the RPC in Reno relating to Unit 6, and the murderer's otherwise enigmatic valedictory is a picture of that same project. Without any special knowledge, this pattern suggests that the reason for the lengthy hiatuses between events is that the murderer was not in the Bay Area at all (where the police were looking for him) except in connections with business relating to that project. With the exception of the murders in December 1968 and the two events in March 1971, the Zodiac chronology runs exactly parallel to the Unit 6 chronology. It must be pointed out that the planning work on Unit 6 had been underway in the Bay Area since 1967. The brief comeback in March 1971 was obviously motivated by a need to respond to the Riverside story, a response which could not be made from outside the Bay Area (or the state) without tipping the murderer's hand. I cannot go any farther than this in print without wading through a mess of legal tripwires. But I think that I can safely point out that all the planning work on the Boise Cascade projects at Lake Tahoe was done by a major consulting firm situated in another state, and that the two commercial greeting cards the Zodiac sent to the Chronicle had as their themes, in this order, a fountain pen and a dragon.
Editor's Note: The production of 12:22, a film about Gareth's pursuit of Zodiac, has been announced. It is being produced by Joseph Clapsaddle (don't laugh; he did "Come Back to the 5 & Dime, Jimmy Dean, Jimmy Dean"), with filming to begin in April 1984. Locations will be in San Francisco, Boston, and Oxford. Anyone for the Mensa Crowd Scenes?