Meet the lead investigators on the hunt for the Zodiac Killer

The lead investigators in The Zodiac Killer: Case Closed? are Sal Labarbera and Ken Main. Both are world-class detectives with years of experience under their belts, Sal in the LAPD and Ken in the Marine Corps. We sat down with them to explore the latest case that confronts them, catching the Zodiac Killer.

Why does this case still capture the public imagination?

Sal: Because it's still an unsolved investigation, this is a fifty-year unsolved case. There have been so many serial killers throughout US history lots which have had a resolution, but this is like our modern day Jack the Ripper.

Ken: It was the way he taunted police, he wrote these cryptograms which would put him at, in my estimation, above average intelligence. So the public start thinking, here you have a person who kills at random, who is above average intelligence and is taunting, that makes for a very scary individual. I think that's the reason Zodiacs lore still exists today.

Is it right to say that codes put Zodiac was in complete control?

Sal: Correct, you don't tend to get a serial killer who writes letters to the police, family members and the press. But our code team are on the case. These guys are the best in the world. They've developed a computer programme that is specifically designed for the Zodiacs codes and have been working on it for years. What's helped them now is having Ken and me on the ground interviewing those involved and looking at police reports. We then feed this information back to the code team which enables them to develop more clues and more ways to crack the code.

The two of you, the code breakers and the police, make for a great team.

Sal: Oh yeah, as I said these guys are the best in the business. You've got Kevin Knight, who leads the team, a professor at USC, one of the guys worked for Google, another worked for the NSA and is maybe the first they're getting actual facts, data and information that they're able to feed into the computer. So far, all they've had is the codes, now we can add more things to the mix.

Have you ever worked with codebreakers before?

Sal: I've never worked with codebreaking teams before, but then I've never had a case that involved this type of code. So this has been very challenging and exciting for me.

Why do you think the Zodiac Killer was never caught?

Ken: Various reasons, one being the jurisdictional problems. He killed in different places and there wasn't as much communication back then between different law enforcement as there is today. Also, he killed at random remote locations, apart from the Paul Stine murder and after that, he was almost caught. We believe he stopped killing after that. I think all those things lead to the reason why he was never caught. I also think he was lucky. The technology we have today just didn't exist back then.

Sal, at one point in the series you say, "You've got to get down and dirty to crack the case," what do you mean by that?

Sal: It means, not only looking at the original police reports and interviewing detectives and people that were involved but also getting to the crime scene. Put yourself in those footprints, walk the same path that the suspect walked, see what they saw. Even though the environmental conditions man have changed these crime scenes are still out there. An investigator has to put themselves in the place of the suspect, be in his boots. That's getting "down and dirty."

How did you deal with the challenge that so much time has passed?

Ken: While time can create challenges in an investigation, I think that generally, it helped us. For example over time loyalties change, people are more likely to give up information now then they were fifty years ago. For evidence purposes, we have new technology now. If a suspect just touches a piece of clothing, we can now have the DNA and identify. So time can really help, and it did really help Sal and me in the Zodiac investigation.

How do you not give up on a case that has gone cold?

Sal: You have to think about the victims, the families and all the people that are affected by murder. One murder can affect hundreds of people, whether it be the family members, witnesses or the police. In this case, because of the time, the torch has been passed along by so many.

Whats the difference between an investigator from then and now?

Ken: There's not that much of a difference, the only thing is resources and technology. Now we are able to do DNA testing, I'm fairly confident that if San Francisco Police Department had DNA technology back in 1968 they would have caught Zodiac. He wasn't not caught because of a lack of effort, they worked extremely hard on this case back then. That should never be taken away from the investigators.

Sal: In my time working with other detectives and agencies, we are all the same. We have the same drives and whether that be fifty years ago or the present day, homicide detectives just have a drive not to stop. They speak for the voiceless, we are speaking on behalf of the victims.