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The Case Against DNA 166

Hugh Pickens writes "Thanks to fast-paced television crime shows such as CSI, we have come to regard DNA evidence as incontestable. But BBC reports that David Butler has every right to be cynical about the use of DNA evidence by the police. Butler spent eight months in prison, on remand, facing murder charges after his DNA was allegedly found on the victim. 'I think in the current climate [DNA] has made police lazy,' says Butler. 'It doesn't matter how many times someone like me writes to them, imploring they look at the evidence... they put every hope they had in the DNA result.' The police had accused Butler of murdering a woman, Anne Marie Foy, in 2005 — his DNA sample was on record after he had willingly given it to them as part of an investigation into a burglary at his mother's home some years earlier. But Butler has a rare skin condition, which means he sheds flakes of skin, leaving behind much larger traces of DNA than the average person. Butler worked as a taxi driver, and so it was possible for his DNA to be transferred from his taxi via money or another person, onto the murder victim. The case eventually went to trial and Butler was acquitted after CCTV evidence allegedly placing Butler in the area where the murder took place was disproved. Professor Allan Jamieson, head of the Glasgow-based Forensic Institute, has become a familiar thorn in the side of prosecutors seeking to rely on DNA evidence and has appeared as an expert witness for the defense in several important DNA-centered trials, most notably that of Sean Hoey, who was cleared of carrying out the 1998 Omagh bombing, which killed 29 people. Jamieson's main concern about the growing use of DNA in court cases is that a number of important factors — human error, contamination, simple accident — can suggest guilt where there is none. 'Does anyone realize how easy it is to leave a couple of cells of your DNA somewhere?' says Jamieson. 'You could shake my hand and I could put that hand down hundreds of miles away and leave your cells behind. In many cases, the question is not "Is it my DNA?", but 'How did it get there?"'"
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The Case Against DNA

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  • Thanks to fast-paced television crime shows such as CSI: Crime Scene Investigation, we have come to regard DNA evidence as uncontestable.

    Why is an unrealistic American television show being referenced about a case in Liverpool by a UK news source? Is horrible American television that prevalent? I'm not seeing The Mighty Boosh referenced in The New York Times in regards to the legalization of marijuana. And who cares if a television show makes the public think DNA evidence is incontestable? That xenophobic vapid televisions series 24 appears to be proof positive justification for torture and Judge Dread style murder but that should not alter the way our courts rule.

    The prosecution in Liverpool Crown Court has no other proof that ties Butler to the murder — showing just how much store they place in the science.

    Okay, congratulations, that has to be the most jaw dropping thing I've read in quite sometime about justice in the UK. Are you serious? DNA should be used as one piece of a very large puzzle used to prove beyond a reasonable doubt that this person was present at some point in time. It is a flawed process and should be used as one piece of many pieces of evidence against someone. If you put that much weight on it, framing someone just became a one step process. Hopefully it will improve but just as hopefully it will always remain as one supporting piece of evidence requiring many other avenues of evidence before a conviction.

  • by bigstrat2003 ( 1058574 ) on Friday August 31, 2012 @01:08PM (#41191937)
    That would only prove where the phone was, not where the person was.
  • by IAmR007 ( 2539972 ) on Friday August 31, 2012 @01:16PM (#41192049)
    Plus, if they had any idea as to how science works, they would know that one datum doesn't constitute reliable evidence at all. Even finding the same DNA in multiple locations doesn't rule out systematic contamination. Multiple types of evidence are needed to confirm causation with anything. It scares me that people's entire lives can depend on methods that would get any scientist laughed out of the room.
  • Willful Frame Jobs (Score:4, Insightful)

    by ThatsNotPudding ( 1045640 ) on Friday August 31, 2012 @01:19PM (#41192075)
    That is what is so terrifying about the police having DNA samples on hand apriori: NO MORE UNSOLVED CASES!! Contaminate the evidence with someone's DNA you already have on hand (if you don't like them for racial, political, or personal reasons, that's just gravy), and bingo! Instant conviction by idiot juries who can't spell GUILTY without using the letters D, N, and A.
  • by betterunixthanunix ( 980855 ) on Friday August 31, 2012 @01:21PM (#41192099)

    DNA should be used as one piece of a very large puzzle used to prove beyond a reasonable doubt that this person was present at some point in time

    Within some error margin, and that error margin is quite a bit higher than you might expect. If you do not exclude identical twins, even if there were no laboratory errors at all, the probability of finding two people with the same DNA profile would be 1 in 1000; when laboratory errors are included in the analysis, that probability can become high enough to pass the threshold of "reasonable doubt."

    Even if we assume no lab errors, no identical twins, and no measurement errors, DNA evidence is still not sufficient. I could plant someone's DNA at a crime scene without too much difficulty (consider how many personal items in your bathroom will have testable DNA on them -- a razor, a toothbrush, a comb). There have been cases of criminals finding ways to substitute another person's DNA for their own, including one case of a doctor who actually managed to hide another person's blood in one of his veins, thus faking his innocence.

    One data point is not enough to draw any sort of conclusion; it might point you in the right direction, but nothing more.

  • by Desler ( 1608317 ) on Friday August 31, 2012 @01:23PM (#41192123)

    Why is an unrealistic American television show being referenced about a case in Liverpool by a UK news source? Is horrible American television that prevalent?

    Because you're being an intentionally obtuse pedant. First of all, the statement said 'shows like CSI' and if you think international crime shows don't use DNA evidence the same way you're quite naive. The specific show wasn't the point and the reason this is a problem is that popular culture shows has inflated DNA evidence as being some 100% accurate measure of guilt such that juries now will demand DNA evidence in order to even fathom the idea that the persn was guilty. Also, theynare easily misled by DNA evodence in wrongfully convicting people since they don't understand the probabilities or other curcumstances involved that could lead to the DNA being at the crime scene. Hell, The Independent in the UK wrote an article about juries being misled by DNA evidence back in 1994.

    Also, yes, CSI has aired internationally for many years with the U.K. being one of those places. Many American shows air internationally. That this is somehow news to you is hilarious.

  • by bigstrat2003 ( 1058574 ) on Friday August 31, 2012 @01:24PM (#41192143)

    I know the standard of proof is "beyond a reasonable doubt" here, but what I raised is a reasonable doubt. It's the owner's phone, so obviously it would have prints all over it. That doesn't really help. And it's trivial for any criminal with half a brain to simply leave their phone at home, so it's extremely reasonable to doubt the phone's location as proof of the owner's location.

    The phone can be used as corroborating evidence to back up evidence that already shows the person was at home (or wherever), but it's useless by itself. And if you have the other evidence, you hardly need to know where the phone was. So in either case, the phone's location is kind of a moot point.

  • by reub2000 ( 705806 ) on Friday August 31, 2012 @01:51PM (#41192507)

    Okay, from watching crime shows, I've seen a plenty of episodes where DNA evidence is left by a person who turns out to not be the killer. These shows like to play fast and loose with forensic technology, but if the crime could be solved instantly using some magical technology like DNA how would the script writers fill up a 40 minute show? In fact one episode of Lie To Me centered around the main character leaving DNA on the victim. Are people really getting that DNA evidence proves guilt from TV shows?

  • by Jane Q. Public ( 1010737 ) on Friday August 31, 2012 @01:56PM (#41192555)

    "It scares me that people's entire lives can depend on methods that would get any scientist laughed out of the room."

    I have been saying this for years. It is ridiculously easy to contaminate or even plant DNA. Fingerprints are relatively hard to fake, and they don't "accidentally" move from place to place. However, DNA does accidentally move from place to place. Worse: drop a few skin scrapings or spit from someone in the right places, and watch the police foam at the mouth in rabid excitement.

    It's worse than ridiculous. It's a tragedy that doesn't need to exist.

  • Learn please (Score:3, Insightful)

    by Yakasha ( 42321 ) on Friday August 31, 2012 @02:00PM (#41192597) Homepage
    "Anything you say can and will be used against you in a court of law."

    These are not magic words. It is a statement of fact. The emphasis I've added is what is important to you (IANAL, but nobody needs to be to understand the basics).
    There are only a couple, very easy to remember, things that should come out of your mouth when talking to law enforcement of any kind if you want to avoid being detained for 8 months for something you didn't do:

    1. Name, Date of Birth, address of residence.

    2. Am I being detained / Am I free to go?

    3. I cannot speak to you without my lawyer present.

    That. Is. It.

    Don't be a jerk to cops, but do not offer information. Even if they ask nicely.

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