Gregory Haugevik stated "This was the only scene in which there were essentially zero witnesses.. Killer could've been wearing a costume a la Lake Berryessa for all we know...".
This has been touted before, but flies in the face of everything we have come to assume about the Zodiac murders. His first two murders were completely different to his third attack at Lake Berryessa. But were they?. We know nothing of the murder of David Faraday and Betty Lou Jensen, other than where the evidence, and eyewitnesses, either side of the crime, point us. Unlike the final three attacks, there were no direct witnesses to the Zodiac Killer at the actual crime scene, while it was in progress.
The suggestion being, we simply do not know for sure the Lake Berryessa attack was a 'marked deviation' from the Lake Herman Road double murder, we just assume it was. He may have been carrying a knife. He may have been carrying a 'pencil flashlight' attached to his gun, which furthermore may suggest, there was never an intention to use a knife, otherwise why go to the effort. The 'pencil flashlight' may have been a back up, for 'just in case' purposes. But what is certain, is that we cannot say definitively, the Zodiac Killer was not wearing a costume at Lake Herman Road on December 20th 1968 and by the same token, claim the Lake Berryessa attack on September 27th 1969 was the first time the Zodiac Killer got dressed up to execute his cold blooded murder.
**Thanks to Gregory Haugevik