How the Grim Sleeper serial killer was caught thanks to groundbreaking DNA science (Pt 2)

Added: 2026-06-01

[00:00:05]In Los Angeles, detectives have arrested a 57-year-old ex police mechanic in connection with the murders of 10 people.

[00:00:12]>> At about uh 9:20, we made an arrest here in the 1700 block of 81st Street of uh the suspect that uh has been known to many as the grim sleeper. Uh the suspect is Lonnie David Franklin. He's 57 years of age. That particular case was a watershed event in expanding the use of DNA.

[00:00:37]Before that, you needed to have a biological sample from a suspect and be able to compare it to somebody in in a database to put it together because uh you're you're at a crime scene, a murder scene, and there's some blood or semen or what what have you at the scene. You test it, get a DNA result, put it into the this COTUS database, this national DNA database, and if somebody is in that database who had been convicted of a crime, have a match here.

[00:01:27]There was never a match. And what the the cops up in Northern California did, which was a first, was that they went to I I I don't know how they got the idea if the the people who were doing genealogy went to the police or vice versa, but anyway, there was a a connection and they they decided that it may be possible by looking at aspects of the DNA collected at the crime scene to look at portions of that DNA and compare it to a close relative of the individual.

[00:02:09]Uh so this takes a lot. It's not a straightforward thing. You need to have people who are familiar with uh with uh dealing with these uh uh relationships between generations of family members, these genealogologists and also have some somebody there who is also familiar with the DNA. At the time there was these were two very distinct areas and this has since kind of begun to consolidate and uh after doing a whole bunch of testing they finally found an individual that had some features that was a close relationship to uh the suspect.

[00:03:03]Uh the police began to do some old-fashioned police work and they figured out that it this this particular individual could be the suspect in in the case that they're looking for and they started to follow him and I guess they they followed him to a a coffee shop. I don't I don't know if it was a a Winshells or a uh whatever.

[00:03:31]and he had a cup of coffee and he threw the cup uh away at when he finished with it. Uh the police were right behind there. They fished it out and they did typing on the cup on the saliva on the cup from the individual and bingo, it was him.

[00:03:52]So that that was a a huge turnabout from the way DNA had been done before. It it just opened up all kinds of new possibilities that uh were were just dreams prior to that.

[00:04:13]>> Um and yeah, now it's common practice to trail someone until they drop a piece of gum on the ground or a cup in a trash can. uh and now it's common practice to go to the genealogy websites where people have uploaded their you know to find out what their you know background is and all that right >> but it's it's it continues to be an issue of um having big brother looking over your shoulder there are uh lots of people in our community and in across the country for that matter that worry about the government having that much information about your genetic profile, >> right? And that there's a reasonable argument there because if you if you imagine that DNA at some point is going to be able to tell if you are predisposed to a particular disease.

[00:05:13]And if insurance companies can get access to that information, they may not want to sell you insurance. or say it's a pre-existing condition and you're just not covered.

[00:05:29]So the you just can't dismiss it out of hand to say that these people are just misguided. They do have a a point and the solution to this is to have enough government controls and oversight that it's not misused.

[00:05:48]>> Right? So the grim sleeper turned out to be a guy named Lonnie Franklin Jr. uh and he was active primarily uh in kind of south central LA. I believe he was killing sex workers primarily. He was convicted and he um he ultimately died in prison I think from an illness.