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French Police Unsure Which Twin To Charge In Sexual Assaults 626

An anonymous reader writes "In a real life Prisoner's Dilemma taking place in the French city of Marseille, twin brothers have been arrested for a string of sexual assaults. While say they are sure that one of them committed the crimes (corroborated by a standard DNA test), police were told that it would cost upwards of €1m euros (£850,000, $1.3m USD) to distinguish between them using DNA evidence."
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French Police Unsure Which Twin To Charge In Sexual Assaults

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  • by Anonymous Coward on Friday February 15, 2013 @08:00PM (#42917789)

    "Prisoner's Dilemma" does not just mean "a dilemma involving prisoners"

  • by TheRealMindChild ( 743925 ) on Friday February 15, 2013 @08:18PM (#42917987) Homepage Journal
    This isn't reddit. There is no karma train
  • by ifiwereasculptor ( 1870574 ) on Friday February 15, 2013 @08:29PM (#42918103)

    All joking aside, though, I also got curious. And, as I went to Google College, unlike some underprivileged folks, let me share my inaccessible knowledge: []

  • Re:Coercion (Score:5, Informative)

    by shaitand ( 626655 ) on Friday February 15, 2013 @08:38PM (#42918207) Journal
    Here in the Red States of America the prosecution is allowed to specifically threaten you with any ridiculous charges they want to get you to accept a plea bargain. Somehow coercion is allowed for both the police and the prosecution.
  • by popo ( 107611 ) on Friday February 15, 2013 @08:39PM (#42918223) Homepage

    Ah. So there is a way. Thanks for the Google Fu.

    Unlike some 'other' underprivileged folks I have one of those modern "cut and paste" operating systems. :p

    Here is the important bit from the above link:

    "Just like our fingerprints, the environment can change our DNA too. We all build up mutations in our DNA over time. Most of these DNA changes are harmless although some can lead to diseases like cancer.

    Where do these changes come from? Some come from the stuff our body does everyday. For example, we all start out with a single cell and end up with somewhere around 50 or 100 trillion cells.

    The DNA in all of these cells needed to be copied (not 100 trillion times but a lot). The machinery in our cells that copies our DNA is incredibly good at what it does, but not perfect. Occasionally, it makes a mistake that is not fixed.

    Our DNA also changes in response to things like sunlight or the food we eat. Both can damage the DNA causing mistakes to happen.

    Coming up with a genetic test looking for these changes is going to be tough. First, these changes are pretty rare. Everyone has about 100 new mutations in their DNA. Sounds like a lot but spread out over 3 billion base pairs, that is quite a needle in a haystack."

  • by TheSync ( 5291 ) on Friday February 15, 2013 @08:41PM (#42918243) Journal

    My understanding is that identical twins -- arising from the same zygote -- are genetically identical. Not just "pretty much identical" as the article states.

    Then your understanding is wrong, see this article []:

    Geneticist Carl Bruder of the University of Alabama at Birmingham, and his colleagues closely compared the genomes of 19 sets of adult identical twins. In some cases, one twin's DNA differed from the other's at various points on their genomes. At these sites of genetic divergence, one bore a different number of copies of the same gene, a genetic state called copy number variants.

    It is generally felt that copy number variation (CNV) between MZ twins is generally post-meiosis (i.e. mitosis).

    Typical police forensic genetic tests look for a "fingerprint" based on lengths of DNA when cut by particular enzymes. This is unlikely to find CNVs.

    Some CNVs might be discoverable with a SNP microarray chip (not super expensive to perform), but it is possible that you may need to do a complete sequence of both twin's DNA to find the needed CNV differentiator.

  • Re:Coercion (Score:5, Informative)

    by Anonymous Coward on Friday February 15, 2013 @08:50PM (#42918341)

    Whereas in the good, honest Blue States of America, we just threaten hackers for political gain until they commit suicide. Much less expensive.

  • by Anonymous Coward on Friday February 15, 2013 @09:16PM (#42918547)
  • by vakuona ( 788200 ) on Friday February 15, 2013 @09:58PM (#42918797)

    Logic fail.

    If the evidence says one of them did it, and they both deny it, then both are implicitly accusing the other brother.

    Now, if I was the innocent brother, I wouldn't be liking my brother very much. But the innocent brother is telling the truth, and the guilty brother is lying.

    Now, if the innocent brother is covering for the other, then that is another story, but nothing I have seen so far suggests that the twins are covering for each other.

  • by stymy ( 1223496 ) <pdezuviria@g[ ] ['mai' in gap]> on Friday February 15, 2013 @11:17PM (#42919155)
    How is one lying for the other? Presumably, they are both insisting they are innocent, and one of them actually is.
  • by coma_bug ( 830669 ) on Friday February 15, 2013 @11:40PM (#42919273)

    And the innocent person lacks such a right even in the US.

    wait. what? here is the fifth:

    No person shall be held to answer for a capital, or otherwise infamous crime, unless on a presentment or indictment of a Grand Jury, except in cases arising in the land or naval forces, or in the Militia, when in actual service in time of War or public danger; nor shall any person be subject for the same offense to be twice put in jeopardy of life or limb; nor shall be compelled in any criminal case to be a witness against himself, nor be deprived of life, liberty, or property, without due process of law; nor shall private property be taken for public use, without just compensation.

  • by Cyberax ( 705495 ) on Saturday February 16, 2013 @12:54AM (#42919617)
    Analysis cost is about $20k per genome for good enough coverage to distinguish CNV (and I work for a DNA sequencing company).
  • by chebucto ( 992517 ) on Saturday February 16, 2013 @12:57AM (#42919627) Homepage

    This is the prisoner's dilemma:

    Two people commit a crime.

    Both are arrested, but there is no physical evidence.

    They are put into separate rooms and each offered a deal:
    1 year in prison for you, and 10 years for your partner, if you admit to the crime first

    If either of them admits to it, they both go to jail - because they both took part in the crime. If they both stay silent, they both go free. However, each has a strong incentive to admit to the crime, because the other person might admit to it first.

    In this case, however, only one person might be guilty. If that's the case, the innocent party has no incentive to rat the guilty one out. The essence of the prisoner's dilemma is lost.

  • by c0lo ( 1497653 ) on Saturday February 16, 2013 @05:13AM (#42920511)

    Ever heard of a plea bargain?

    Not in France, no.

    Fine, ever heard of plaider coupable.

    Non. Mais, avec l'aide de l'ami Google [], je peux vous montrer quelques informations pertinentes:

    Dans la pratique, cette procédure est surtout utilisée pour traiter rapidement la masse des délits routiers, comme le défaut d’assurance ou la conduite en état alcoolique, ainsi que les délits simples, comme les petits vols.
    La CRPC n’est toutefois pas applicable à certains délits ou certaines accusations particulièrement graves. Parmi ceux-ci : les violences, les menaces, les agressions sexuelles et les atteintes involontaires à l’intégrité de la personne, pour lesquelles une peine d’emprisonnement d’une durée supérieure ou égale à 5 ans est encourue.

    In english translation - with the help of google, here you have some relevant information:

    In practice, this procedure is mainly used to quickly treat thje majority of traffic offenses, such as lack of insurance or drunken driving, as well as simple offenses such as petty theft.
    Though, the plea bargain is not applicable to some serious offenses or allegations. Among them: violence, threats, sexual assault and involuntary damage to the integrity of the person, incurring a sentence of imprisonment for a term no less than 5 years.

  • by Tom ( 822 ) on Saturday February 16, 2013 @06:05AM (#42920685) Homepage Journal

    A ball-peen hammer or garden sheers to the knuckles works wonders

    [citation required]

    All the evidence I have seen indicates the opposite. Torture is a horribly ineffective means of finding the truth. In fact, throwing a coin is probably better.

    If it isn't obvious why, the very simplified causation is roughly this: As torture proceeds, the goal of the victim becomes very simple: Make it end, no matter what. We KNOW that people will readily admit to crimes they did not commit under torture, including crimes that carry the death penalty. We know that people under torture reach a point where they would not only say "yes" but also thank you for it if you offered to kill them right then and there. We know that they will invent not only details of the crimes they are being questioned about, but also entirely new crimes.

    We have historic evidence of people admitting crimes under torture where later investigations found conclusive evidence that they could not possible have committed them.

    Torture does not work if your goal is truth.

  • Re:Coercion (Score:5, Informative)

    by cffrost ( 885375 ) on Saturday February 16, 2013 @06:56AM (#42920829) Homepage

    ... and that's why those of us in civilised countries consider the US to have a similar legal system to the brutal Sharia law of countries like Afghanistan, Somalia and Mali, among others.

    There are those of us in the US who agree that the US legal/penal/justice systems are brutal, regressive, unjust, and counterproductive, and do what we can to change that, but at the same time are opposed by authoritarian-types who claim that various improvements proposed by "bleeding-heart liberals" equate to being "soft on crime." However, my state struck down the judicial death penalty a few years ago and decriminalized marijuana possession last year, so I still have hope that improvements can continue, at least at the state level.

The trouble with the rat-race is that even if you win, you're still a rat. -- Lily Tomlin