We have previously examined the possibility of a phone call being placed after the Lake Herman Road double murder at the exact same payphone located at Springs and Tuolumne, described as a 'crank call' by Pierre Bidou. It was determined, that this being the Zodiac Killer, it had the possibility of shifting the time of the Lake Herman Road murders approximately 5-6 minutes earlier than previously thought, allowing the killer to head in the direction of Vallejo before Stella Borges left her ranch and declaring that she had passed no vehicles en route. After the first two attacks the killer would be heading toward Springs Road on both occasions, turning west and heading for the payphone to place his call, before taking refuge at his residence. The early murders of a serial killer are more likely to be closer to home, before he gains in confidence and ventures further afield, placing the area around the payphone of great interest.

Michael stated two things in the police report. Firstly: "Subject appeared to be short, possibly 5'8", was real heavy set, beefy build. States subject was not blubbery fat, but real beefy, possibly 195 to 200, or maybe even larger. Stated he had short curly hair, light brown, almost blond. He was wearing a short-sleeved shirt, blue in color. Cannot remember if it was light or dark blue." Secondly: "States that he tried to climb over the back seat to get away from the shooting and subject kept shooting him again and again. States subject finally quit shooting him and apparently turned the gun on Dea and started shooting her again and again. States subject then turned around and started to walk back to his vehicle which still had the headlights on. Michael stated he could not tell if he meant to yell at the subject or if he just yelled from pain, but he let out some kind of yell. At this time, the subject apparently hearing him, came back to the car and shot Michael two more times, once in the back and once in the left leg. States the subject then turned the gun on Dea and shot her twice more." This final action by the killer may unwittingly have changed the course of the next 40 minutes.
The time of the year couldn't have been more different from the Lake Herman Road attack - the murders at Lake Herman Road committed in sub-zero temperatures of 22 degrees Fahrenheit, and Blue Rock Springs in very agreeable temperatures that averaged above 80 degrees Fahrenheit for much of the day, which is why the killer was described as "wearing a short-sleeved shirt, blue in color" - something he was unlikely to have been wearing the night of December 20th 1968. It is my guess the assailant's shirt was relatively light in color, and when Michael Mageau "let out some kind of yell", it forced the killer into something he hadn't planned to do - interact closely with the crime scene.

The first shots at Michael Mageau struck him in the neck (facial area) and once in the shoulder, before he clambered over the seat to the rear of the vehicle in an attempt to escape the initial barrage. The killer also fired three direct shots at Darlene Ferrin, but struck her far more. Michael Mageau would have been bleeding heavily at this point, more than likely coating the passenger seat in blood as he clambered over it to seek refuge in the rear of the vehicle. The killer after firing five shots, retreated, but after hearing Michael Mageau yell, returned to the vehicle and leaned into the open window and over the front passenger seat, in all likelihood smearing blood on his "light blue short-sleeved shirt" and arms from the top of the seat. To angle the gun, striking Michael Mageau in the lower regions, and leaving two spent casings on the rear floorboard of the Corvair, he likely had to lean a reasonable distance into the vehicle. He then delivered the final two shots into Darlene Ferrin. This final action by the killer may very well have created blood transfer to his shirt and body, and ultimately transferred it to his vehicle. The wise choice, is now, not to make his planned phone call immediately after departing the scene of the crime, exiting his vehicle and entering the payphone covered in blood, but to travel home and get cleaned up, thereby minimizing the obvious risk when placing the call.

Nearly one month later, the Zodiac sent three coded segments in three letters on July 31st 1969 to the San Francisco Examiner, San Francisco Chronicle and Vallejo Times-Herald, giving details of the first two crimes to prove he was the actual killer. However, the Zodiac Killer was doubted as to whether the letter writer and killer were one and the same, and Vallejo Police Chief Jack E Stiltz still wanted more proof, as detailed in the Saturday August 2nd 1969 San Francisco Chronicle. He requested the writer to send a second letter "with more facts to prove it." This may have proved the perfect opportunity for the killer to switch the emphasis away from his home locality.
He created the perfect phantom witness of a "negro about 40-45 rather shabbly dressed," who he would not only describe in unnecessary detail, but fortunately a witness that would verify twice that Zodiac was in a car - and it was brown in color. The Zodiac Killer has never been so forthcoming. By placing himself in his vehicle, he gives the impression he could have lived anywhere, as opposed to a killer who probably walked to the payphone. The unaccounted time between the Blue Rock Springs attack and the placement of the phone call, may be indicative of a killer cleaning himself up and removing the blooded clothing, resulting from his return to Darlene Ferrin's Corvair for the final four shots. And Michael Mageau was the trigger.
Kim Rossmo talked about the possible home locations for the Zodiac Killer using Rigel: "There's a number of possibilities. But remember, Rancho Vallejo was possibly 26,000 people at that time, of which only 13,000 will be male, and only a certain proportion of those are of the correct age, and a certain portion of those are only going to be white. Then we start looking at the neighborhoods involved, we have a pretty small subset. Then we start combining that with some of the personal and behavioral descriptors, and then we work in the vehicle information. If this case was active today, it would not be too difficult to find this person." Apply this to a 20 minute walking radius of the payphone and you can see it's a very real avenue of investigation, if you can acquire the details of residency. Zodiac Killer-Geographic Profiling.
See also: A Stone's Throw Away.