The Fairfield letters (now proven to be authentic  } were mailed to the San Francisco Chronicle on December 7th 1969 and San Francisco Examiner on December 16th 1969 (four days before the Melvin Belli letter), the latter of which contained a small fragment of code and an attached drawing of a knife dripping with blood, entitled The Bleeding Knife of Zodiac. The opening gambit of the December 16th letter uses the line "this state is in troulbe..I will go for the Goverment life", suggesting a shift in the Zodiac Killer's thinking to more high profile targets. Law enforcement operates primarily through governmental police agencies in the United States, so the threat to target "government life", bearing in mind his threat to kill 38 cops at the foot of this letter and to kill "a cop" in the December 7th 1969 Fairfield letter, it's a reasonable assumption that "government life" = cops.
Featured in the letter as a primary target was Sacramento, central to the murders of Judith Hakari on March 7th 1970 and Nancy Bennallack on October 25th 1970. Judith Hakari had been working at the Sutter Hospital in Sacramento on March 7th 1970, from where she had traveled home in the late night hours and pulled into the parking lot of the Markston Apartments, the location of her suspected abduction. One and a half months later, her body was discovered in a shallow grave alongside Ponderosa Way in Weimar, Placer County. She had been horrifically beaten about the face, strangled and raped.
Shortly after the disappearance of Donna Lass on September 6th 1970 and two days prior to the Halloween card, on October 25th 1970, Nancy Bennallack, a court reporter was found brutally stabbed numerous times at the Tahitian Apartments only a block away from the Markston Apartments. If this was the Zodiac Killer, it would suggest a marked deviation from his previous four canonical attacks, having never given any significant clues in his communications that he was involved in either the Bennallack or Hakari murders, other than a weak link in the March 22nd 1971 Pines card and the pasted text of "pass Lake Tahoe areas". Nancy Bennallack is described as strikingly similar in appearance to Judith Hakari, and the close proximity of the two crimes has understandably given rise to the idea of one perpetrator.
A letter mailed on May 6th 1986 claiming to be from the Zodiac Killer, detailed a further crime in Sacramento not too far from the Markston and Tahitian Apartments. The 1986 letter to the San Francisco Chronicle was without doubt describing the brutal murders of Koy Ien Saechao (48) and Choy Fow Saelee (40) as they presumably rested in their parked car by a Sacramento freeway. See here.
The Fairfield letter, showcasing his Bleeding Knife of Zodiac with seven drops of blood (one for each victim) was very likely incorporating the murders of Kathie Reyne Snoozy (15) & Debra Gaye Furlong (14) on August 3rd 1969 in San Jose, which he had just claimed on November 8th 1969 by the addition of "Aug" in the Dripping Pen card. The Lake Berryessa attack on September 27th 1969 was the only crime committed thus far by the Zodiac Killer with a knife, but he was again falsely claiming the Snoozy & Furlong murders and celebrating the fact by creating this imagery. It was always questioned why the Zodiac failed to brag about his theatrical crime on the shoreline of Lake Berryessa, bearing in mind it was his most unusual and daring to date. There is no definitive answer, but the Zodiac Killer never foresaw that he was to leave one surviving witness, namely Bryan Hartnell. He could have bragged endlessly about this crime, but in retrospect, his failure to kill both victims actually played right into his hands, because the detailed account of Bryan Hartnell, the description of the killer's costume and the extensive newspaper accounts gave him all the publicity he could ever have wished for. However, newspaper accounts were starved of the full details, in that the by knife attribution on the car door of Bryan Hartnell's Volkswagen Karmann Ghia was withheld from the public domain in order to flush out the real killer from any subsequent hoaxers. Although, during the middle of December, the "by knife" details were released in newspapers as far reaching as New York and Ohio.
This communication was certainly mailed by the Zodiac Killer, as was the other Fairfield letter mailed on December 7th 1969. In the December 7th communication, the author stated "I just need help. I will kill again so expect it any time now. The will be a cop. Then I will Turn myself in OK." Both Fairfield letters were withheld from the newspapers, yet on December 20th 1969 the Melvin Belli letter would arrive, with a plea to "please help me" three times.
If that wasn't enough, just three days after the second Fairfield letter, on December 19th 1969, somebody claiming to be the Zodiac Killer rang police dispatcher Shirley Searey at the San Jose Highway Patrol station issuing two threats that mirrored the contents of the Fairfield letter (despite the fact it was unpublished).
The Fairfield letter, mailed on December 16th 1969, contained the totals of police he wanted to kill. It also contained a picture of a dripping blade entitled The Bleeding Knife of Zodiac. This was effectively an extension of his "by knife" attribution on the car door of Bryan Hartnell at Lake Berryessa on September 27th 1969, glorifying in the fact he was responsible for the brutal stabbing of Bryan Hartnell and Cecelia Shepard alongside the Knoxville Road, as well as the frenzied murder of Kathie Snoozy and Debra Furlong on August 3rd 1969 in San Jose, which he would ultimately claim by the listing of "Aug" in his running victim count on the Dripping Pen card.
The second Fairfield letter was clearly still in his mind (probably angered by its failure to be published), when he made the phone call to Shirley Searey at the San Jose Highway Patrol station on December 19th 1969. He now wasn't threatening to kill one cop in San Jose, he had upped that total to five, more in line with the rest of his list on December 16th 1969. The caller stated "I am going to kill five of you officers and a family of five between now and Monday". The phone call to the San Jose Highway Patrol station and the wording of "you officers", shouldn't leave anybody in any doubt as to where the threat was primarily aimed. Bearing in mind The Bleeding Knife of Zodiac drawing and the focus of the threat toward San Jose, we don't have to go very far to conclude which "family of five" he was threatening. The Zodiac Killer was already claiming the murder of Debra Furlong, so why not claim he was going to murder the rest of her family for maximum terror. Whether the police connected the dots is unknown, but it's unlikely he arrived at the figure of five randomly. If you look at the August 6th 1969 article here, you will notice the last two subheadings of "callers" and "children".
Under the banner of "callers" it describes the frustration of Glen Furlong (father of Debra) to the many annoying phone calls the family received, stating "On several occasions people have called and as soon as we answer, they hang up," He said his neighbors were "very sympathetic", but complained he found some of his phone calls "very disconcerting". Under the banner of "children" it lists his remaining children of Glen, 16; Floyd, 12, and Pamela, 11. With the Zodiac Killer having read this San Francisco Chronicle article (his inspiration for the Berryessa attack and 1971 Monticello card), it isn't very surprising that the "family of five" threatened by phone on December 19th 1969 would be Glen Furlong and his wife, along with their three children of Glen, Floyd and Pamela.
We have further proof that the these two letters were mailed from the Zodiac Killer, thanks to David Oranchak, Sam Blake and Jarl Van Eycke. A 38 character code accompanied the Fairfield letter on December 7th 1969, just twenty-nine days after the Zodiac Killer's recently deciphered 340 cipher. This code contained only characters available in the 340 cipher, unlike the following 13-Symbol and 32-Symbol ciphers. This opened the door to the possibility that the 38 character code was somehow related to the 340 cipher and maybe contained a clue to its construction. Druzer, an avid and diligent Zodiac researcher, mailed me the 38 character code deciphered with the 340 cipher key. The result is mostly garbled, but he drew my attention to the final line of both codes ending in "death". The Zodiac Killer only took a 4+ horizontal combination of characters from the 340 cipher to the 38 character code on two occasions. Those were HER> and AIKꞮ+, which spelled the standalone words of IRON and DEATH, before the diagonal shift was applied to the 340 cipher to reveal the message. Despite the last two rows of the 340 cipher being a mixture of forward and backward reading words, the word "death" sits at the end of both the 340 and 38 character ciphers, indicating that this word likely concludes the message of the rearranged final two lines. It could mean that the final sentence of the 340 cipher is "life is death" rather than "death is life".
Other horizontal words do exist in this format, however, the Zodiac Killer gave us 4 and 5 characters which bound the 340 and 38 character ciphers together, and both formed English words. The Zodiac Killer began and ended his 38 character code with two prominent sections from the start and end of the 340 cipher, both of which contained visible words before any shift was applied (the final word remaining static). This may be another observation, which confirms to the doubters the December 7th 1969 letter as an authentic Zodiac communication. Unless of course, the 38 code hoaxer identified two passages of 4 and 5 characters from the undeciphered 340 cipher, that just happened to accidentally find two English words after the 340 key was applied, specifically the two which began and ended the 340 cipher. This hoaxer would also have to guess that by separating the prominent ZO∆AIKꞮ+ characters on the bottom line of the 340 cipher, into AIKꞮ+ on the bottom line of the 38 character code, he would be reducing these characters to create something meaningful. He apparently did. By separating these characters into the five visible at the end of the 38 character code, he created the word "death", just like the solved 340 cipher. Druzer pointed out the same thing, stating "The most curious/compelling feats are that the author isolated actual words, most notably death, and that he refrained from copying Zodaik, which would certainly be expected of a hoaxer". In other words, he dismantled the ZO∆AIK element, while leaving Ɪ+ in place, to form "death" as the final word on the 38 character code. This appears to show knowledge of the hidden message in the 340 cipher. See full article.
The Fairfield Letter was mailed on December 16th 1969, sandwiched between the authenticated Bus Bomb letter of November 9th 1969 and the Melvin Belli letter on December 20th 1969 (both containing a shirt piece from victim Paul Stine). . The lack of shirt piece, along with its amateurish design has led many people to question the validity of this correspondence with respect to the Zodiac Killer. But they are wrong, as shown by the multiple arguments outlined above and in the article presented below.
The Zodiac Killer, after murdering Paul Stine in Presidio Heights on October 11th 1969, mailed three pieces of Paul Stine's shirt to the newspapers. The first shirt piece was mailed to the San Francisco Chronicle on October 13th 1969, just two days after his murder in Presidio Heights, with another being mailed on December 20th 1969 to the home residence of prominent attorney Melvin Belli. However, a third piece was mailed in tandem with the Bus Bomb letter on November 9th 1969, outlined in the FBI files and two articles written by the San Francisco Chronicle. The mailing of three portions of Paul Stine's shirt is evident from photographs of the shirt published on the Zodiac Killer Facts website marked A, B and C.
THE FAIRFIELD TWO
We will take a further look at the two letters mailed from Fairfield to the San Francisco Chronicle on December 7th 1969 and the San Francisco Examiner on December 16th 1969. Many have dismissed these two communications as having been penned by the Zodiac Killer, but this couldn't be further from the truth. These two communications were undeniably mailed by the Zodiac Killer.
The article on the left appeared in the San Francisco Chronicle on December 28th 1969, regarding the letter mailed to attorney Melvin Belli on December 20th 1969. It states "The Zodiac Killer-unheard of in recent weeks - is back in operation and pleading for help before he takes his ninth and tenth victims".
The Melvin Belli letter was mailed only 13 days after the December 7th 1969 San Francisco Chronicle 'Fairfield' letter, so it appeared as though the Chronicle had effectively dismissed the Fairfield letter as genuine correspondence from the killer, claiming they had not heard from the Zodiac "in recent weeks". The Fairfield letter was not published in the newspapers - and the follow up letter on December 16th 1969, mailed to the San Francisco Examiner, equally failed to make little impact. Why were these communications apparently overlooked?
Many Zodiac researchers and enthusiasts regard the two Fairfield letters to have been penned by a hoaxer - but if the letters were created by a hoaxer why did he do such a poor job as to negate the purpose of sending them. The Zodiac Killer created two organized and structured ciphers of 408 and 340 characters. Both were designed with care, using seventeen characters in each row, and a form of 'filler' on the 408 code to keep the cipher symmetrical. The December 7th 1969 Fairfield letter contained a 38 character code, much of which was 'stolen' from the 340 cipher and formed into scruffy disorganized rows. If the letter writer was attempting to disguise himself as Zodiac, then why didn't he simply create a few lines of symbols in an organized fashion like the 408 and 340 cipher? The fact he didn't do this, in all likelihood suggests that he wasn't trying to pass himself off as Zodiac - because he was Zodiac. The argument, is that the December 7th 1969 letter is a poor Zodiac imitation and therefore not the Zodiac. It isn't very difficult to copy any of the characters from the first two ciphers and create a new and realistic looking cipher that mimics its predecessors. This is not a difficult task - and neither is the handwriting. The following image (December 7th 1969 Fairfield letter and 38 character code) was inspired by a forum thread on Zodiac Killer Site.
The December 7th 1969 letter stated "I just need help. I will kill again so expect it any time now. The will be a cop. Then I will Turn myself in OK." If this letter was by a hoaxer and not published in any newspapers, then how was the Zodiac Killer able to know its contents?
The December 20th 1969 Melvin Belli letter was confirmed Zodiac correspondence, as it contained a piece of Paul Stine's blooded shirt. The Melvin Belli letter pleaded for assistance "Dear Melvin. This is the Zodiac speaking. I wish you a happy Christmass. The one thing I ask of you is this, please help me. I cannot reach out for help because of this thing in me won't let me. I am finding it extreamly dificult to hold it in check I am afraid I will loose control again and take my nineth & posibly tenth victom. Please help me I am drownding. At the moment the children are safe from the bomb because it is so massive to dig in & the triger mech requires much work to get it adjusted just right. But if I hold back too long from no nine I will loose complet all controol of my self & set the bomb up. Please help me. I can not remain in control for much longer".
Can it be argued that the Fairfield letter stating "I just need help" and the Melvin Belli letter thrice urging "please help me" just 13 days later, was just simple coincidence, or is it more likely the Zodiac Killer had written the earlier Fairfield letter and was just continuing the theme. In addition, the second part of the December 7th Fairfield letter is threatening to kill a cop just like the communication following the Belli letter on April 20th 1970, in which Zodiac suggested "there is more glory in killing a cop than a cid because a cop can shoot back". Additionally. the Fairfield letter after stating he "needs help," intimates he "will kill again," as does the Melvin Belli letter when warning he "will lose control again".
Now let us approach this from a different angle and consider the possibility that the December 7th 1969 letter was featured in the Fairfield Daily Republic newspaper, or some other publication prior to the Zodiac Killer composing the Melvin Belli letter. The Zodiac Killer certainly appeared to design his ciphers in a carefully structured way - so imagine - that when saw this poorly designed and crude 38 character code plagiarizing his 340 cipher in a newspaper - why on earth would he then validate the hoaxer by mimicking the December 7th 1969 letter by stating "please help me" in the Melvin Belli letter later that month. One would think he'd have wanted to disassociate himself from it. Whichever approach you pursue, tends to validate the December 7th 1969 letter mailed to the San Francisco Chronicle, and by association, the December 16th 1969 letter mailed to the San Francisco Examiner, which was almost certainly penned by the same author. The latter Fairfield letter could also have links to the 'Halloween' card, with the code reading Death By Fire, By Gun, By Rope and By Knife. link
Much has been made of the single postage on both the Fairfield envelopes, the writing paper used by the author and the crudeness of the two short codes. However, there could be a perfectly reasonable explanation for all these anomalies. The Zodiac Killer thought he had sent proof of his connection to the first two crimes when he mailed the trinity of July 31st 1969 letters. Vallejo Police Chief Jack E. Stiltz urged the author for more details to prove he was the killer, and the Zodiac duly obliged on August 4th 1969. The Zodiac then mailed a piece of taxicab driver Paul Stine's shirt in his next three consecutive and 'confirmed' communications. Firstly, in the October 13th letter, secondly, with the November 8/9 card and letter, and finally with the Melvin Belli letter.
All these communications were mailed from San Francisco, likely during his normal routine - but the December 7th & 16th letters were mailed from Fairfield. If he was away from his usual residence during this span of 10 days (possibly having broken up for Christmas) and was on holiday, or visiting family, or simply away from his home location on business, then it is conceivable that he had to improvise with writing paper and stamps. He most certainly would have stored the blooded shirt piece in a secure location (possibly at home), to which he likely had no access during the mailing of the two Fairfield letters. These letters have all the hallmarks of 'spur of the moment' communications while away from his home location. This may explain their deviation from what had come before or after.
1963 June 4th-The Domingos/Edwards Murders
1966 October 30th-The Cheri Jo Bates Murder
1966 November 29th -The Confession Letter
1966 December- The Riverside Desktop Poem
1967 April 30th- Bates Had to Die Letter
1968 December 20th-The Lake Herman Murders
1969 July 4th-The Blue Rock Springs Attack
1969 July 31st- Vallejo Times-Herald Letter and
408 Cipher Page1 (solved)
1969 July 31st- Examiner Letter and
408 Cipher Page 2 (solved)
1969 July 31st - Chronicle Letter and
408 Cipher Page 3 (87% solved)
1969 July 31st-The Complete 408 Cipher
1969 August 4th- Debut of Zodiac Letter
1969 August 10th- Concerned Citizen Card
1969 September 27th- Lake Berryessa Attack
1969 October 7th- The Good Citizen Letter
1969 October 11th-The Presidio Heights Murder
1969 October 13th-The Paul Stine Letters
1969 October 22nd-Call to Chat Show
1969 November 8th-The Dripping Pen Card and
340 Cipher (solved in 2020)
1969 November 9th-The Bus Bomb Letter
1969 November 19th- The Riddler Notes
1969 November 21st-The San Jose Code Letter
1969 November 28th-The Betsy Aardsma Murder
1969 December 7th-The Fairfield Letter
1969 December 10th- Forecast for Cancer
1969 December 11th- Forecast for Leo
1969 December 16th-The Fairfield Letter
1969 December 20th-The Melvin Belli Letter
1970 Feb 21st- The Hood and Garcia Murders
1970 March 22nd-The Modesto Attack
1970 April 15th-The Robert Salem Murder
1970 April 20th-"My Name is" Letter,
Cipher 3 and Bus Bomb Diagram
1970 April 28th-The Dragon Card
1970 June 26th-The Button Letter
Cipher 4 (solved in 2019) and Map
1970 July 4th-The Sleeping Bag Murders
1970 July 24th-The Kathleen Johns Letter
1970 July 26th-The Little List Letter
1970 Sept 6th-The Donna Lass Disappearance
1970 October 5th-13 Hole Postcard
1970 October 17th- "You Are Next" Postcard
1970 October 27th-The Halloween Card
1971 March 13th-The Los Angeles Letter
1971 March 22nd-The Pines Card
1971 Unknown- The 148 Character Cipher
1971 July 13th-The Monticello Card
1973 August 1st- The Albany Letter
1974 January 29th-The Exorcist Letter
1974 February 3rd-The SLA Letter
1974 May 8th-The Citizen Card
1974 July 8th-The Red Phantom Letter
1974 December 27th- Christmas Card
1975 November 3rd- The Belmont Letter
1978 April 24th-The 1978 Letter
1978 May 2nd- The Channel Nine Letter
1978 July 19th- The Scotch Tape Letter
1981 March 8th- The Peachtree Letter
1986 May 6th- The Freeway Letter
1987 October 28th- The 1987 Letter
1988 February 1st- The McDonald's Letter
1988 February 8th- The McDonald's Letter 
1990 September 25th- The Celebrity Cypher
1990 December-American Greetings Card
2001 January 10th- Happy New Year Card
Unknown DMV Letter (possibly November 1971)