Even if Leonardo da Vinci had truly, as legend claimed, blurred Salvator Mundi's left eye with his palm, there was no way to determine that the palm print belonged to Leonardo da Vinci.
Just as the fingerprints found in the phone booth did not necessarily belong to Zodiac, it had been a public phone booth used by many people. Likewise, the fingerprints recovered from Paul Lee Stine's taxi were insufficient as evidence.
After Leigh Allen was arrested, the police compared his fingerprints and handwriting, but naturally, they did not match. He could write with both hands, and his left- and right-handed handwriting differed. What was more, when the police asked him to write, he deliberately wrote very large, making it impossible to match his writing to Zodiac's.
People with split personalities could have different handwriting as well. In short, there was no direct evidence proving that Leigh Allen was Zodiac. The police were unwilling to let him go so easily, so he was sent to a psychiatric hospital.
There had been many eyewitnesses in this case, including two police officers. Dan Fouke observed a white man walking along the sidewalk. The encounter lasted a full five to ten seconds, but the emergency radio dispatch had only told them to look for a Black suspect rather than a white one. They had no reason to speak to the man, so they passed him without stopping.
Later, Dan drew the criminal's face from memory, and it did not resemble Leigh Allen either. There was no compelling evidence whatsoever proving Leigh Allen was that man!
The dispatcher responsible for that mistake believed a taxi robbery had taken place. According to police statistics, African Americans and Latinos committed far more robberies than white people, and the same was true of shootings. Serial killers, meanwhile,