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The Courts United States

Brain-Scan Lie Detection Rejected By Brooklyn Court 197

blair1q writes "A judge in Brooklyn has excluded Functional Magnetic Resonance Imaging (fMRI) lie-detector evidence from a trial there. However, the decision will not set a precedent, as it was made without even conducting a hearing on the method's validity, but on the principle, argued by the defense, that 'juries are supposed to decide the credibility of the witness, and fMRI lie detection, even if it could be proven completely accurate, infringes on that right.' That principle can be tested in later hearings, such as one scheduled for May 13, 2010, in Tennessee; in this case, the defense wants to use fMRI evidence it has already collected to prove its client is innocent. fMRI has been shown to be 76-90% accurate. That number seems significantly larger than the rate of false convictions."
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Brain-Scan Lie Detection Rejected By Brooklyn Court

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  • by LostCluster ( 625375 ) * on Thursday May 06, 2010 @04:07PM (#32116442)

    The Supreme Court has given science the legal definition that a "beyond a reasonable doubt" equates to 99.9% certainty... a system that is wrong 10% of the time or more needs at to at least be much times more accurate before it's going to be trusted. You're only allowed one blooper in 1000 by this standard. Nice tech, but it's not there yet.

  • by Anonymous Coward on Thursday May 06, 2010 @04:17PM (#32116632)

    Yeah, just ask the salmon []

  • Lie Detection (Score:5, Informative)

    by Adrian Lopez ( 2615 ) on Thursday May 06, 2010 @04:28PM (#32116810) Homepage

    Calling these devices "lie detectors" is misleading at best. Until they invent a machine that can travel back in time and compare the suspect's claims against the facts, there can be no lie detectors. All a lie detector can do is make visible certain physiological responses that are more or less associated with lying. While sometimes these responses are explained by the fact that the person is lying, humans are complex enough that it should never be considered a trustworthy mechanism as far as the law is concerned. Juries are easily influenced by apparently scientific evidence, but lie detection is a questionable science at best and could prejudice juries against the defendant.

    There's an episode of Penn & Teller's Bullshit that does a good job of putting the lie to the lie detector.

  • by Nidi62 ( 1525137 ) on Thursday May 06, 2010 @04:31PM (#32116842)
    I mean come on, fMRI has even been used to definitively prove that dead fish can think! ( How much more scientific proof for its accuracy do you need?
  • by Shadow of Eternity ( 795165 ) on Thursday May 06, 2010 @04:38PM (#32116916)

    Wrong again. Polygraphs can only tell when the subject is showing physical signs of stress through pulse, blood ox, temperature readings, and galvanic skin response.

    Maybe I am stressed, I had a bad burrito and I'm terrified that the next fart won't be silent or dry.

    An FMRI "lie detector" only shows you what parts of the brain are active on the assumption that certain parts lighting up mean someone is thinking too much and thus making it up.

    Maybe my brain IS active, that one girl had some really nice breasts and I wonder what they look like underneath all that clothing...

  • by linzeal ( 197905 ) on Thursday May 06, 2010 @04:40PM (#32116948) Homepage Journal

    Well perhaps we need a check on the jury's seemingly endlessly ability to be lured into convicting innocent people out of motley assortment of prejudices and 'gut-feelings'. You can't tell me the fact that across the world minority conviction rates are higher for the same crimes because of anything but bigotry. Don't even start with the idea of ever person having the right to appeal, which can take years if not decades to overturn a wrongful conviction.

    If this technology can get to 9X.x% accuracy in the near future I would like it to at least be used to prevent people from having to go to trial or have charges brought against them in the first place. District Attorneys have far too much power right now to prosecute people charge them with 5 crimes that can result in years in prison and 10's pf thousands of dollars for petty crimes like vandalism and than have them plea down to 30 days in jail and a 1000 dollar fine.

    My friend in his last year of college was walking home from his art studio down town with all of his art supplies in a backpack near a bank downtown. A rent a cop came out of nowhere and started accusing him of vandalizing the property and started manhandling him and moments later the real cops showed up and arrested him. Why, well he had marker pens in his backpack that were the same type used to write anti-capitalist graffiti on the bank's ATM and someone had superglued the deposit door shut. He was held over night was forced to call his parents for bail, had all of his art supplies confiscated, charged with 3 misdemeanors that could of landed him in jail for 2 years, fought all the charges with a private attorney his parents paid for, lost all the charges got 6 months in jail and a 3500 dollar fine, appealed the conviction, found evidence that another bank in the area after he was arrested had the same graffiti done to it while he was with his parents 100 miles away, went to trial and the judge spent 3 days grilling him on his political activities before overturning the convictions. He got back his art bag, everything was either broken in half or torn and it smelled like feet because it had been locked up with his shoes for over a year at this point. He told me it took over 25,000 dollars to prove he was innocent and if he did not have well off parents he would of been in jail.

    Public defenders in this country on average handle over 500 cases a year whereas a DA handles half that, something has to change or more and more of us are going to be going to jail as innocent men. In NYC the average case load of a public defender is 720 cases a year.

  • by wembley fraggle ( 78346 ) on Thursday May 06, 2010 @04:43PM (#32117010) Homepage []

    fMRI is a fairly arcane art- it's nowhere near the "thought detector" most laypeople think it is. The actual practice is rife with the chance to show confirmation bias, given the kind of data filtering that goes on during the process. Check out the link above- scientists were able to show the reaction that a fish had to watching pictures of pleasant situations (babies, puppies, flowers, etc). The fish was dead at the time of the test, however. So, if fMRI can be used to show that a dead salmon has feelings, I'm not likely to trust it for a "lie detector".

  • by droopus ( 33472 ) * on Thursday May 06, 2010 @04:43PM (#32117014)

    While we're on the subject of the "law..."

    Anyone ever hear of relevant conduct as the feds consider it? Basically it means that your custody can be affected by behavior for which the charges have been dismissed, or even charges for which you were acquitted.

    I kid you not. Here's a true scenario:

    A man gets caught with five grams of crack. (FIve year mandatory minimum in the feds, until the crack/powder disparity is corrected.) That's five years for about a sugar packet of rock. But when he is arrested,the cop says" hey you look like the guy that hosed down that McDonald's with an AK47, killing 35 schoolkids!"

    Of course, you aren't, you go to trial, and after 30 seconds of deliberation, the jury acquits you of the mass murder charge. But you still go away for the crack.

    Here's the kicker: when you go to prison, the Bureau of Prisons (BOP) considers the murders "relevant conduct" and sends you to a very nasty pen, puts extreme violence on your record, and puts a Public Safety Factor on you, because of the "relevant conduct"...of which you were acquitted. Due process? Hah!!

    Don't believe me? []

    Want the official Government position? []

    The US justice system is a fucking travesty, and unfortunately, you don't realize that till you're neck deep in it.

    Be careful out there.

  • by linzeal ( 197905 ) on Thursday May 06, 2010 @04:47PM (#32117070) Homepage Journal
    What if they choose to have the fMRI done? You can still have lie detectors admitted in some jurisdictions so why shouldn't the defense be allowed to use this tool? No one is forcing anyone to do the fMRI in this case.
  • by chill ( 34294 ) on Thursday May 06, 2010 @04:48PM (#32117098) Journal

    Without proper correction, fMRI has been shown to detect brain activity in a dead fish []. Next up, trial lawyers.

  • by blueg3 ( 192743 ) on Thursday May 06, 2010 @04:50PM (#32117120)

    Of course, nobody actually suggested just administering a lie detector test to everyone in the area. They only suggested allowing the results of the lie detector to be admitted into evidence.

  • by mangu ( 126918 ) on Thursday May 06, 2010 @05:12PM (#32117416)

    The right to remain silent is meant to make sure no one can be forced to speak under torture. It does not mean you have a right to keep authorities from getting evidence against you. This means, for instance, that police can force you to take a breath or blood alcohol test.

    If it weren't for the right to remain silent, the police could tell you "say you are drunk or I will break all your teeth" but it would be meaningless for them to say "breath here with a BAC of 0.20 or I will break your teeth".

  • by nomadic ( 141991 ) <> on Thursday May 06, 2010 @05:17PM (#32117476) Homepage
    Actually the story you link to says the sentencing judge can take into account charges the defendant was acquitted on, but implies that the ultimate jail sentence can't be extended past the maximum sentence for the charge they were convicted on.
  • by Monkeyman334 ( 205694 ) on Thursday May 06, 2010 @05:32PM (#32117628)
    Gosh. Legal issues are frustrating to discuss on Slashdot. People don't have the right to remain silent. You have the right to not incriminate yourself in court. That means if you are the target of an inevstigation you can be given immunity and forced to talk. If you are a witness and not the target you can be forced to talk. You can be forced to take a breathalizer test because it's not testimonial. None of this has anything to do with this case.
  • by naasking ( 94116 ) <> on Thursday May 06, 2010 @06:33PM (#32118506) Homepage

    You can also defeat the statistical problem by repeating the test a statistically significant number of times.

  • Memory doesn't exist (Score:3, Informative)

    by DrYak ( 748999 ) on Thursday May 06, 2010 @07:52PM (#32119684) Homepage

    For the last time, there's not really such a thing as "Memory" in a human's brain.
    We are not machines with a RAM storage or a tape recorder in the head.

    We only function in terms of what is plausible and coherent given a set of rules and what is not. This is why it is entirely possible to convince someone of false memories (The book "Elephants on Acid: And Other Bizarre Experiments" has a couple of them cited).
    For another example, you don't remember meeting Mickey Mouse in Disneyland because you have a Video clip of it in your head-VCR, but because Mickey Mouse and Disney get often along together and associated mentally (and whole bunch of other such associations which all together make up the whole memory). And its entirely possible, by suggestion, to make people remember they met Bugs Bunny in Disneyland (Well, not here on /., but some people were there only as very young and - as not big fan of cartoons - only have the association that Disney is usually cartoonish and that the rabbit is a toon).

    The only thing that you can see is if the person is giving an information in which the person is believing (i.e.: an information which the brain considers coherent given the set of rule), or if it is something that has the person thinking (building the information on the go).

    But the machine could be wrong and make a false negative if the person is really believing the false information (see the false memories experiments, as the "lost in the market" example from the book, these persons could very easily show up as "is not telling a lie").
    And the machine could give false positives if the person has to think and deduce *true* information (for example giving a PIN or a password when the person has bad memory and doesn't remember the code directly but uses mnemonic).

    The machine can only distinguish when highly associative area or planning area are slightly more used - that doesn't tell you a damn thing about whether something is true or not. Only which mental process were used to come up with the information. The fact that some a slightly more often used when coming up with a lie doesn't tell you much about the true/false status of said information.

  • by L4t3r4lu5 ( 1216702 ) on Friday May 07, 2010 @05:10AM (#32123816)
    In the UK you cannot be forced to provide a specimen of breath for blood alcohol analysis. Failing to do so is a crime, with identical penalties to providing a positive reading of greater than 80mg/100ml blood alcohol (35g/100ml breath), being a mandatory 12 month driving ban and a fine of (typically) £300-£400. However, failing to provide a sample will often include discretionary increases in the duration of a ban, or a much heavier fine.

    Forcing a suspect to provide a sample would be assault. It's that simple. However, this is totally off-topic and nothing to do with fMRI Mens Rea tests.
  • by Anonymous Coward on Friday May 07, 2010 @09:08AM (#32125210)

    Moral of the story: Never obey a rent-a-cop.

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