
But the question still remains, he made a phone call 40 minutes after the attack, when it could conceivably have been made as early as 12.10 am. So what was the Zodiac Killer doing during this timeline. Was he disposing his weapon nearby or at home, was he parked up somewhere or just driving aimlessly around in the night.
There are good reasons to believe the killer was a resident of Benicia as the driving time to this location for the safe disposal of the weapon and a turnaround time of 10 minutes, takes us back to the payphone at Springs and Tuolumne at approximately 12.40 am. But if he was a resident of Vallejo, a home location somewhere in the vicinity of the payphone is equally credible, particularly as some have suggested, he walked back to the Springs and Tuolumne intersection as a means of drawing less attention to himself. It has also been noted that prime suspect Arthur Leigh Allen's residence at 32 Fresno Street was only half a mile or as little as 9 minutes walking distance from the payphone. A journey time to Fresno Street from Blue Rock Springs Park is about 10 minutes, the walk to the payphone is 9 minutes, leaving a turnaround time of 21 minutes, had the killer gone straight home to this residence.
But the question remains, if the killer was a resident of San Francisco and headed for home immediately after the Blue Rock Springs attack, where is the logic applied to the missing 40 minutes and the choice of payphone. Are we to assume he drove around randomly in the night or sat in his car for a notable period of time, made the call to Nancy Slover, then departed for San Francisco.

Of course it would be presumptuous to exclude San Francisco based on this analysis alone, as there are other possibilities, but if the Zodiac Killer's first thought was to head home after the Blue Rock Springs attack, this choice of payphone has relevance. Had the Zodiac Killer headed across the bay, he would still have had a thirty plus mile journey ahead of him to the safety of home, seemingly in contradiction to traveling west towards the heart of Vallejo, some 40 minutes after the attack and placing a phone call, that inherently could have been made from anywhere.
** Your opinion is valued and any theories or counter arguments can be placed in the comments section below.
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