He never did anything of value to corroborate his involvement in the murder of Kathy Snoozy and Deborah Furlong. He merely insinuated he was their murderer by dropping "Aug" into his Dripping Pen card on November 8th 1969 and bumping up his total victims from five to seven. The Zodiac Killer, at this juncture, was effectively leaving himself an escape clause if these murders were ever attributed to the real killer. His vagueness was evidence of deception, unlike his four canonical attacks, which he backed up by near irrefutable proof of his involvement.
On June 26th 1970, the Zodiac Killer would repeat this tactic by insinuating his involvement in the shooting death of Sgt Richard P. Radetich (25) on June 19th at 5:25 am, who was gunned down by three shots from a .38 caliber revolver at point blank range through the driver side window of his vehicle while in the process of serving a parking ticket. He was sat in his police car near 643 Waller Street in San Francisco. The Zodiac Killer once again left himself an escape clause if Sgt Richard Radetich's real murderer was ever apprehended. Rather than write "I shot a cop sitting in a parked car with a .38" which is a little more specific, he merely stated "I shot a man sitting in a parked car with a .38". The Zodiac Killer avoided inextricably binding himself to the crime by leaving the door half open.
On September 26th 1970, the San Francisco Chronicle ran an article about the missing (believed abducted) nurse Donna Lass in South Lake Tahoe on September 6th 1970, and the murder of nurse Judith Hakari, who was abducted on March 7th 1970 and discovered in a shallow grave aside Ponderosa Way in Weimar nearly two months later. But why did the Zodiac Killer latch onto this newspaper story?
This newspaper publication had all the ingredients the Zodiac Killer could possibly have wished for. He didn't want to appear too eager to claim either of these crimes, not only because the immediacy of the claim would have looked forced, but Donna Lass had only been missing for twenty days at the time the San Francisco Chronicle article featured and she may have turned up unharmed. Investigators feared Donna Lass may have been abducted, just like the abduction and eventual murder of Judith Hakari six months earlier. The Zodiac Killer had just come off the back of being linked with the abduction of Kathleen Johns in Tracy, California, so the story of these two women was the perfect opportunity to spread his terror into Placer County and Nevada.
Lake Tahoe borders Placer County, so when the Zodiac Killer mailed his Pines card on March 22nd 1971 with the words "pass Lake Tahoe areas", he was effectively leaving the Pines card open to interpretation. He could be insinuating his involvement in the abduction of Donna Lass from the Sahara Tahoe Hotel & Casino, which bordered the lake, or he could be insinuating his involvement in the abduction and murder of Judith Hakari from the Sutter Hospital, who was ultimately discovered in a shallow grave in Placer County. "Pass lake Tahoe areas" could be referencing the burial site of Donna Lass or Judith Hakari - or both. By leaving the Pines card intentionally vague in description, the Zodiac Killer is effectively introducing to the observer the idea of three abductions into his portfolio of crime, all of whom were young women, of which, two were nurses with an unfortunate connection to the lake. The Zodiac Killer knew by mailing the Pines card in such an unspecific way, that investigators would make the connection between these crimes, but yet again, the Zodiac Killer had left the door ajar if any of these crimes by the lake were solved, and subsequently proven not to be the Bay Area murderer. The vagueness of the Dripping Pen card, Button letter and Pines card are telling. They are a complete departure from the specificity exhibited by the Zodiac Killer's actions during and after Lake Herman Road, Blue Rock Springs, Lake Berryessa and Presidio Heights - and indicative of a man who was lying about Snoozy & Furlong, who also had no hand in any of these 1970 crimes.
He would again bide his time, before begrudgingly uttering the words "I do have to give them credit for stumbling across my riverside activity, but they are only finding the easy ones, there are a hell of a lot more down there". The Zodiac Killer seemed surprised that investigators had stumbled across his Riverside activity, but probably not half as surprised as when Paul Avery presented him with another murder to add to his growing portfolio. His acceptance speech in the March 13th 1971 'Los Angeles' letter, yet again replete with vaguness and a ready made get out clause. He could easily have stated "I do have to give them credit for stumbling across my riverside library murder, but they are only finding the easy ones, there are a hell of a lot more down there", but used the word "activity" as a less than full confession. I chose the word "confession" carefully, because the Zodiac Killer left the door open to being responsible for the Riverside letters on November 29th 1966 and April 30th 1967, and nothing more.
He then cements the notion of involvement by claiming "a hell of a lot more down there", when he hasn't given us one shred of evidence he was the murderer of Cheri Jo Bates. The Zodiac Killer didn't supply one piece of evidence in his 'Los Angeles' letter only known to him and Riverside police, just like the Confession letter author did 4 1/2 years earlier. Riverside activity doesn't equate to Riverside murder - and neither does boasting about more murders in Southern California as a way to validate the crime you haven't yet proven. There was a sea change in Zodiac activity after the October 11th 1969 Paul Stine murder, from a ruthless killer, to a killer who wanted to appear ruthless. But he did remain consistent subsequent to October 11th 1969, in that he always left the back door open, clutching his escape clauses firmly between his grubby hands.