Just watched David Fincher's Zodiac. (Fincher is another director everyone should know by name, and doesn't. He directed Se7en [over-rated] and The Social Network [under-rated], among other things.) Watched this, and cross-referenced occasionally with Robert Graysmith's book, and even bookmarked Donovan's "Hurdy Gurdy Man" as it's so haunting. Cleaned the office and checked the Sox game while I was at it. I do more when I'm doing more.
Anyway, I was struck by how much of a labyrinth these types of cases are. It seems (more so from the movie than from the book) that 95% of the "evidence" is a series of interesting dead ends that lure the driven like the Sirens to their obsessive destruction. Certainly a few of the real-life men were driven to near-insanity (and temporary insanity) by this case. Yet when all was said and done, it's like what Hannibal Lecter said: "We covet that which we see every day." Find the first victim; find who knew and possibly lived near the first victim; find out who fits the profile of the evidence presented. (Bob Starr, one of the more likely suspects, lived 50 yards from the first victim, and knew her.) In other words, keep it simple. Play the odds. Don't play politics.
And don't fuck up the evidence, or the crime scenes.
I say this last because I thought of the JonBenet Ramsay and O.J. cases throughout the movie. Tons of suspects and red-herrings. Screwed-up crime scenes; tampered evidence. I just saw an episode of Autopsy in which the head coroner said the same thing: both murder scenes were tampered to the extent that cops were leaving bloodied handprints and shoeprints all over the place. (The coroner said he spoke up right away about there being two killers. He thinks O.J. was one of them.) Anyway, these cases remain unsolved, either truthfully unsolved, or, as in the case of O.J.'s, "unsolved," because a) the cops screwed up the crime scenes and the gathering of evidence; b) the cops played politics, fought over jurisdiction, didn't share all the evidence with each other; c) the cops screwed up the interviews; d) the cops got carried away by interesting red-herrings (although, of course, they rightfully don't know this until the dead-end moment happens); e) too much time passes and people die and/or forget things; f) evidence gets lost...
You get the idea. A labyrinth nightmare. The Zodiac case and the JonBenet Ramsay case are similar in these ways, as the Green River case and maybe the Ripper case was as well. In the latter two, as I believe also with the Zodiac case, the cops knew who the most-likely killer was but were unable to officially charge or arrest him for a plethora of reasons. Such cases are an Odyssey of obsessive, nightmarish proportions. No wonder they're not solved.
And a great quote from Graysmith's book, I found almost at random: "I have a therapist who says, 'The trick is to learn you can't corral all the rattlesnakes,'" says Fincher. "'You just got to know where they are.'"