The general public tends to believe that these claims must be true because they appeared in a best-selling book, a popular film, or a TV news report. However, the facts tell a very different story about Allen, and these facts strongly indicate that Allen was not the Zodiac.
The documents examiner for the San Francisco Police Department said that he was given "a banana box full of Allens handwriting and it wasn't even close".
That means the probability of Allen changing his handwriting that much was remote, as the examiner would have noticed the examples over time changing.
InDNA analysis, again, "wasn't even close", along with another suspect that they checked. No handwriting match, no DNA match does not mean there isn't enough evidence, it means he didn't do it!!!!
Eyewitness testimony is the LEAST reliable form of evidence there is, it has been proven as such many, many times. As far as the ton of circumstantial evidence, or as I like to call it, "coincidences", I am sure you all have done extensive researching online, as have I, and you can come up with a million coincidences a day with names, dates, etc.
So, in answer to your question of "how could they let him run around with so much proof? You might even venture to ask yourself a question as to why the hell the issuance date of his drivers license would be important?
That kind of evidence gathering is junk, plain and simple. People have watched too many detective shows with the "whodunit" themes, seriously. Take down your family's birthdates and pick some dates of major happenings in the world and see if you can match any up.
Do it with SS numbers, car license plates- any numbers you choose and you will find an astonishing number of coincidences. Same goes with names, like them mentioning that the cab dropped the Zodiac off at the "Allen apartments".
You would not believe how many times things like this occur. Type random names into google and see how many things pop up, like typing in "Scott Anderson" and watching the results show you how many thousands of people across the country that are named Scott, live on Anderson St.
Put it this way - there are no strange coincidences, there are plenty of common ones! In fact, I challenge anyone to pick numbers, names, etc and see if they can NOT find any coincidences.The exculpatory evidence for Arthur Leigh Allen seems overwhelming.
His handwriting does not match.. His fingerprints do not match.. His DNA does not match..
On top of this Arthur Lee Allen was mostly bald and did not wear glasses. Nor did DNA extracted from the envelopes (on the Zodiac letters) come close to Arthur Leigh Allen."  While police often use document examiners during investigations, court rulings on the scientific validity of handwriting analysis have been mixed to negative.
Nor did DNA extracted from the envelopes (on the Zodiac letters) come close to Arthur Leigh Allen."  While police often use document examiners during investigations, court rulings on the scientific validity of handwriting analysis have been mixed to negative.
The principle suspect in both the book Zodiac and its film adaptation of the same name, Zodiac ( Fincher), Arthur Leigh Allen, was heavily implicated as the Zodiac Killer. The film’s closing credits make note that Allen may have been exonerated by a partial DNA mismatch.
I’ve linked a story from the San Francisco Weekly disputing this story. Arthur Lee Allen = Primed Suspect. Armstrong told Bawart that "handwriting samples of Arthur Leigh Allen were submitted to handwriting experts with known writings of the Zodiac killer.
Experts indicated that the handwriting was similar but definitely was not that of the Zodiac killer." Analysis of the discs failed to uncover any. Apr 07, · Tit Willow Zodiac = Arthur Leigh Allen Exorcist Letter Zodiac Killer Solution Zodiac-Killer I believe that a trail of visible handwriting clues throughout this correspondence, the "SLA" card.