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Familial DNA Testing Nabs Alleged Serial Killer 258

cremeglace writes "A quarter-century of conventional detective work failed to track down the killer responsible for the deaths of at least 10 young women in south Los Angeles dating back to the mid-1980s. But a discarded piece of pizza and a relatively new method of DNA testing has finally cracked the case, police announced last week. On July 7, L.A. police arrested Lonnie Franklin Jr., 57, a former garage attendant and sanitation worker they suspect is the serial killer nicknamed the 'Grim Sleeper.' The key evidence? A match between crime-scene DNA and the suspect's son, obtained by a search through the state's data bank of DNA collected from 1.3 million convicted felons."
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Familial DNA Testing Nabs Alleged Serial Killer

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  • by coolsnowmen ( 695297 ) on Monday July 12, 2010 @06:17PM (#32879922)

    The moral of the story is: finish your damn pizza.

    • Re: (Score:3, Interesting)

      by dlanod ( 979538 )

      It's the usual "DNA testing helped us catch this serial killer. Obviously this means it's all safe and dandy and no privacy worries here!" article that gets wheeled out about once every couple of months, just in case someone was starting to have concerned thoughts about all that identifying material being available to the government and its underlings.

      I'm rather sceptical about these articles these days because they do seem to appear so regularly to remind us all how lucky we are. Keep an eye out and you'

  • by MarkvW ( 1037596 ) on Monday July 12, 2010 @06:18PM (#32879946)

    Familial testing gave them the ballpark family.

    Regular policework found the bad guy from there. They stalked the suspect, who was nabbed after DNA was found on a meal that the suspect discarded. THAT DNA was the stuff that got him busted.

    • by Anonymous Coward on Monday July 12, 2010 @06:23PM (#32880022)

      Moral of the story: Eat the crust.

      • Yes, especially if you're a serial killer. Then you'll get diabetes and die. I mean, after all that serial...

        I wish I could press a button that will kill all the killers.

        Thank you folks, I'll be here all weak.

    • by Goner ( 5704 )

      It was good policework, and prior to that good reportage by one LA Weekly reporter that caught this guy. The high tech nature was used properly I believe. I'd rather see this sort of thing exonerate people than convict them, but given that in 1988 an 18 year old was found dead 10 blocks south of where I live... 99.99% chance killed by this guy... I'm glad he's off the streets.

  • by TheTurtlesMoves ( 1442727 ) on Monday July 12, 2010 @06:19PM (#32879958)
    DNA fingerprints are not as random as many think. The markers used were not designed for a nation wide database situation. Hence collisions could be a big problem. That is two people with the same fingerprint (at least at the very small parts of DNA we look at) can in fact be very likely with a database this size.

    I'm not saying he is innocent, but i don't think we should jump to the conclusion that he is guilty either.

    In fact we may need to use SNPs (Single nucleotide polymorphisms) to be good enough for a database of millions (or eventually billions) to reduce collisions to acceptable levels.
    • In fact we may need to use SNPs (Single nucleotide polymorphisms) to be good enough for a database of millions (or eventually billions) to reduce collisions to acceptable levels.

      Even then there's the problem of sample collection errors, lab errors and so on. A DNA match will never give certainty, just give the police a useful lead.

    • by westlake ( 615356 ) on Monday July 12, 2010 @06:49PM (#32880320)

      DNA fingerprints are not as random as many think. The markers used were not designed for a nation wide database situation. Hence collisions could be a big problem. That is two people with the same fingerprint (at least at the very small parts of DNA we look at) can in fact be very likely with a database this size.

      The collision is a problem only if both are plausible suspects:

      The Korean War vet in a California hospice is almost certainly not the serial rapist and killer who has been stalking women in New Jersey the past six months.
       

      • Re: (Score:3, Funny)

        by simtel ( 798974 )
        You should try telling that to the TSA.
      • by goodmanj ( 234846 ) on Monday July 12, 2010 @11:29PM (#32882996)

        Yes, but often the defendant and *his brother* are both potential suspects.

        This actually came up in a case I served on a jury for. The defense argued that the *other* brother could well have committed the crime, and given the poor quality of DNA evidence, we couldn't disprove that beyond a reasonable doubt.

        DNA collision among close-knit racial groups is worth thinking about; collision within families is a serious problem.

    • That is two people with the same fingerprint (at least at the very small parts of DNA we look at) can in fact be very likely with a database this size. [...] The markers used were not designed for a nation wide database situation.

      Correct, I suppose, but perhaps misleading. Your objection does not, I believe, lead to a rational conclusion that convictions based on false-positives will rise, huge budgets squandered, or other similar troubles occur. Once police are sufficiently interested in a small handful of individuals, after they take the dozens or hundreds of hits from a familial search and narrow them by conventional detective work, I'm sure much more thorough tests are available to conclusively check just a few people against th

    • by sehlat ( 180760 ) on Monday July 12, 2010 @06:50PM (#32880338)

      When you're talking about evidence where the death penalty is at issue, the ONLY acceptable collision rate is zero.

      • by witherstaff ( 713820 ) on Monday July 12, 2010 @07:27PM (#32880830) Homepage
        The feds and states have been working hard to ensure there are no known collision rates above zero by prohibiting searches of the database to see just how bad it is. The LA Times has a nice writeup about the problem. [latimes.com] Basically they don't want scientists doing blind studies because it shows DNA isn't absolute especially for cases that have no other evidence.
      • by wurp ( 51446 )

        From a purely utilitarian point of view, any collision rate that is likely to save more victims (by executing the correct killer) than it kills (by executing the incorrect killer) is a net positive.

        Which is not to say that you shouldn't try to continue to improve your negative failures (false acquittals) and positive failures (false convictions) after you reach that net positive point, but that's the time at which it makes sense to use the results of the evidential method by utilitarian ethics.

        • by Rich0 ( 548339 ) on Monday July 12, 2010 @08:16PM (#32881394) Homepage

          From a purely utilitarian point of view, executing anybody who is likely to consume more than they produce over the remainder of their life is a net-positive for society. That is almost exactly the definition of fascism.

          I'm sorry, if some guy goes out and kills somebody, I can't do anything about that but try to catch him. However, if I support a law that lets my government kill innocent people as long as it is likely that they'll have a net savings of life then I'm the one with blood on my hands.

          I'm not even really a big opponent of the death penalty. However, clearly it can't be applied in a utilitarian way.

          • by wurp ( 51446 ) on Monday July 12, 2010 @08:33PM (#32881520) Homepage

            From a purely utilitarian point of view, executing anybody who is likely to consume more than they produce over the remainder of their life is a net-positive for society.

            I don't think that's true at all. You can treat a human life as something with inherent value, greater than the value of anything else, and use utilitarian ethics to examine life and death issues.

            Why is there blood on your hands if you support a law that lets a government employee kill an innocent, and not blood on your hands when you support a law that lets a criminal kill an innocent?

            I know our gut tells us that when we act and it results in death it's worse than when we fail to act and it results in death, but I think our gut's wrong.

            For more interesting variations, see http://en.wikipedia.org/wiki/Trolley_problem [wikipedia.org]

            • Re: (Score:3, Interesting)

              by treeves ( 963993 )

              I know our gut tells us that when we act and it results in death it's worse than when we fail to act and it results in death, but I think our gut's wrong.

              Such a position is very problematic. For instance, it makes the CEO of a drug company that fails to manufacture and distribute a malaria drug (say for profit-related reasons) worse than Stalin or Hitler, by virtue of more people dying as a result his inaction.
              And how do you decide who's guilty in a case of non-action, since clearly if someone dies as a res

              • Re: (Score:3, Interesting)

                by wurp ( 51446 )

                Which of your examples do you think demonstrates a flaw in my assertion? Obviously people (including me) are not built to act from the heart on the ethical stance I'm talking about, but I see no reason someone in the position to easily stamp out malaria, but who chooses not to do so purely for reason of profit, is any less responsible for those deaths than if he killed them himself.

                Of course, once you start discussing real world examples of that kind of situation, things get much more complicated: the CEO

  • by Anonymous Coward on Monday July 12, 2010 @06:32PM (#32880132)

    Familial searches from a DNA database the size of the one in California are very, very likely to produce false positives. For example, a study of the Arizona CODIS database carried out in 2005 showed that approximately 1 in every 228 profiles in the database matched another profile in the database at nine or more loci, that approximately 1 in every 1,489 profiles matched at 10 loci, 1 in 16,374 profiles matched at 11 loci, and 1 in 32,747 matched at 12 loci. http://www.maa.org/devlin/devlin_10_06.html [maa.org]

    With California currently having the third largest DNA database in the world, the odds of ANY new genetic evidence matching on a cold search is way too likely.

    • Re: (Score:3, Informative)

      by AK Marc ( 707885 )
      They said they had 200 familial matches. They then did investigative work on that to bring the number down, then tested the male Y chromosomes of the matches to see if any matched the Y found at the crime scene. There was one and only one final match. So a two-factor familial test had a zero false positive rate (first markers, plus extra Y testing). Yes, the initial run did get lots of matches, but they tested one and only one person as a result, and he was a 100% match.
  • Most disconcerting.

    Does this mean that if I have had a DNA sample taken, all of my direct ancestors can be traced without ever being a "part" of the DNA database?

    Alternatively, can a descendant of mine provide a DNA sample sometime in the far future and inadvertently "include" me in the system?

    Is there some point in time where the introduction of new genetic material "breaks" this continuity between generations, in terms of DNA as a legal identifier?

    My understanding of genetics simply isn't up to the task o

    • Alternatively, can a descendant of mine provide a DNA sample sometime in the far future and inadvertently "include" me in the system?

      Are you afraid this will make it easier for skynet to find you (now that phone books are passe)?

    • Re: (Score:3, Interesting)

      by AK Marc ( 707885 )
      If you don't want to have your DNA taken, then don't give it to anyone else. That includes progeny. Otherwise, anyone sampling your progeny's DNA will be able to get a guess as to yours. Though in this case, my understanding is that they had his DNA from a crime scene, but not on file. The partial hit got them to narrow down the search to a specific family, where they identified the most likely offender and tested him for a direct match.

      So he left his DNA at a crime scene, then left it on some trash af
  • This means everyone's DNA should be taken.

     

  • Hmmm... we have some DNA... Good, let's just send it to the lab and throw that guy in jail. No need to vet it. Look judge... the DNA matched!!!

    Moral of the story, if your going to be a serial killer you need to find a dupe that is pretty straight and unlikely to have too many dealings with the law and mostly a loner and plant his DNA at all the crime scenes.

  • they had a guy four square for a brutal rape, but the guy was unconcerned. sure enough, the dna test came back and turned out he only shared half the dna with the culprit: the murderer must be the guy's brother

    so they let him loose and track down brother after brother, sample his dna, and it turns out to be yet another brother. meanwhile, the woman who was raped is murdered, and they find a hair on her body that matches the original suspect's dna 100%

    while examining the original suspect again, grissom sees that his skin is strangely mottled, and he has an interesting statue in his house: the legendary greek chimera

    grissom cracks the case: the guy committed the rape because he knew he was a genetic chimera. the dna of his semen was the "brother" of the dna of his blood

    http://www.csifiles.com/reviews/miami/bloodlines.shtml [csifiles.com]

    a genetic chimera is an extremely rare individual in which fraternal twin zygotes are created, then fuse. so different organ lines in the body are from two different "individuals". you are your own twin, you are a mix of two people. there is also the real life case of a woman who became a criminal suspect because she was suspected of kidnapping: she claimed to be the mother of a child, but a genetic test reveals she was the aunt: her own ovaries weren't hers but from her "phantom sister"

    http://abcnews.go.com/Primetime/story?id=2315693&page=1 [go.com]

    not that this is an argument against how they caught the grim sleeper, i applaud this use of genetic profiling of relatives to solve crimes. its simple sleuthwork, and plenty of innocent people come under suspicion all the time in criminal investigations that must be ruled out with basic detective work

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