That night, an empty white 1959/1960 Chevrolet Impala was spotted in the turnout by Robert Connelly & Frank Gasser at 9pm and Bingo Wesner at 10pm. It sat idle in pitch darkness on an extremely cold night (22°F) on two occasions in an extremely remote location, yet there appeared to be no newspaper coverage of this Chevrolet Impala, asking the public if they saw such a vehicle anywhere else in the vicinity that night (or requesting assistance to locate it). Investigators questioned the workers at nearby Humble Oil to see if they passed the turnout that night, therefore common sense should have meant they would have questioned everybody in and around the Benicia Water Pumping Station, including the Marshall Ranch, Frank Dotta Ranch (and others), to determine whether any had an association with an individual connected to a 1959 or 1960 white Chevrolet Impala. This should have been routine police work, yet we have read nothing beyond the sighting of Frank Gasser, Robert Connelly and Bingo Wesner.
At 10pm, Bingo Wesner also noticed the Chevrolet Impala while walking the adjoining field, tending to his sheep. Clearly, this was unlikely a motorist relieving himself on two occasions for an extended period. A furher eyewitness, William Crow, was parked up in the turnout for a brief time between 9:30pm and 10pm, without seeing the Chevrolet. So it's fairly obvious that the driver of the Chevrolet had twice parked up in the turnout that night, and vacated the vehicle on both occasions. The only reasonable conclusion is that its occupant (or occupants) entered one of the surrounding fields. But seemingly, with no follow up regarding this vehicle in the police report, the only logical conclusion is that nobody in the vicinity of the turnout could shed any light regarding its owner. So why is at least one individual wandering the adjoining fields in freezing temperatures in pitch darkness, if not for nefarious reasons?
If this was the murderer's vehicle he would have known this. Therefore, the claims of the August 4th 1969 letter writer stating he used a pencil flashlight for extra illumination, is extremely noteworthy. Extra illumination would not have been required in the turnout when you have the use of headlights from your vehicle, along with the illumination from within each vehicle. Also, extra illumination would certainly not have been required if the murderer had kept the couple penned inside their vehicle. The only person that would have required additional illumination (either carried or gun-mounted) would have been somebody venturing into the fields surrounding the turnout. Such as the driver of the white Chevrolet Impala, who apparently never came forward. There is a distinct possibility that this Chevrolet owner wrote the "Debut of Zodiac" letter, because this person had a viable reason to carry additional illumination as he distanced himself from his vehicle that night. Not once, but twice, on a freezing dark night in Benicia. Possibly an individual, who on July 31st 1969, would promote the idea of hunting humans in the wilderness because it was more fun than killing wild game in the forest.