ZODIAC: One of the Finest Investigative Films Ever Made

ZODIAC: One of the Finest Investigative Films Ever Made 

Zodiac was a 2007 film directed by David Fincher that chronicles the hunt for Northern California's infamous Zodiac Killer during the late 1960s and 1970s.  While the movie is about finding the Zodiac killer, the story revolves around Robert Graysmith.  Graysmith was a newspaper cartoonist who slowly became involved in the investigation.  As the Zodiac continues to taunt police and reporters, causing hysteria in California, Graysmith becomes increasingly obsessed with the investigation, to the point of losing his wife and then his job.  As years go by, the police and press have moved on but Graysmith continues to pursue the investigation, never stopping until he can confirm the killer’s identity.

The most striking aspect of this movie is the difficulty the police had in communicating with other departments.  Zodiac allegedly murdered people in Northern California, with the possibility that there were murders in Southern California.  At the time, police departments had difficulty sharing information they had about their cases.  Investigators attempted to exchange information by telephone, mail, and the emerging technology of fax, but many agencies lacked compatible equipment or established procedures for sharing investigative files.  Graysmith was allowed to visit each police department’s files, but was not allowed to make copies or take notes.  However, Graysmith was able to see (years later) that some key pieces of information were not sent to other police departments.  It’s not a coincidence that the murders were spread out among several jurisdictions, because serial killers at the time were aware of communication difficulties between police departments and intentionally took advantage of them.  Ted Bundy was reportedly aware of law enforcement's communication weaknesses and deliberately crossed jurisdictional boundaries to make investigations more difficult.

Almost all suspects were ruled out because a handwriting expert would compare a suspect’s writing with the notes the Zodiac sent to the newspaper.  There was even a concern with one suspect who was ambidextrous and police believed he wrote the letter with his less dominant hand.  Today, reliance on handwriting analysis is often considered a junk science, in that there is not much science to it.  Unlike DNA evidence, which can identify an individual with an extremely high degree of statistical certainty, the same cannot be said of handwriting analysis.  While trained examiners can identify similarities and differences in handwriting, the discipline lacks the scientific certainty associated with DNA testing or fingerprint analysis. As a result, handwriting evidence is generally viewed as corroborative rather than conclusive.  This evidence may help get a warrant, but it is not going to be the main factor that gets a judge to sign an arrest warrant.

More than fifty years later, the Zodiac murders remain officially unsolved. That lingering uncertainty is what makes Zodiac so compelling. Rather than presenting a conventional crime thriller with a neat conclusion, the film reminds viewers that the justice system sometimes reaches the limits of what evidence can prove. For lawyers, investigators, and true crime enthusiasts alike, that unresolved tension is what makes Zodiac one of the finest investigative films ever made. 

TF’s Notes:  The Zodiac was an unusual case because the murderer never had a consistent method of killing.  A gun was usually used, but so was a knife.  The Zodiac claimed responsibility for crimes that police were certain that he did not commit.  In some of his letters he included a blood-soaked piece of material from one of the crime scenes, clearly tying himself to the case.  Also, in one of the crime scenes the killer left a message on the victim’s car door taking credit for other murders.  However, it seems like the strongest evidence connecting these cases is the letters from the Zodiac to the press.  A prosecutor would almost certainly be forced to prove that every murder attributed to the Zodiac was committed by the same individual before presenting evidence from multiple crime scenes to a jury. If reasonable doubt existed about whether one or more murders were committed by another person, the defense could argue that the State's entire theory of a single serial killer had collapsed.  The defense could argue that the prosecution's overarching theory had collapsed, creating reasonable doubt about whether the same individual committed every homicide attributed to the Zodiac.  It raises an interesting question: if the author of the Zodiac letters demonstrably claimed murders he did not commit, could some—or even most—of the crimes attributed to the Zodiac have been committed by someone else?  The letter writer could have been a sadist who is gratified by creating a sense of fear and panic in the community.  He may have been given the blood-soaked cloth from the actual killer or only murdered that one victim.  Although the movie Zodiac makes a very strong argument as to who the Zodiac was, there are still competing theories of who the Zodiac really was.