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Brain-Scan Lie Detection Rejected By Brooklyn Court
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."
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.
They don't tell you shit, I've taken a couple of them for government work and it depends on the person, and their ability to concentrate. You can easily get false positives and easily beat it if you have the right mindset.
~Mekkah
fMRI has been shown to be 76-90% accurate
That's certainly better than a weatherman but not good enough to convict someone.
If it is better than what we have for false convictions than why prefer human prejudice/error over machine error.
Because one of the reasons we have a jury system is to provide a check and balance on the ability of the government to lock people up. Jury nullification may be a bad word in the modern legal system but it's still there.
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
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.
"In prison you just have to shut your eyes and take it. Here you have to shut your eyes and give it."
http://dsc.discovery.com/fansites/mythbusters/db/human-body/beat-lie-detection-test.html
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.
An Education is the Font of All Liberty
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.
"The pie shall be cut in half and each man shall receive.....death. I'll eat the pie."
This sort of thinking (that if the accuracy rate is improved enough it will become a valid way of determining someones guilt) shows a fundamental misunderstanding of statistics. It is the same reason blanket drug testing doesn't work and medical screening can sometimes be a bad thing.
Let's imagine for a moment that this lie detector technology has been perfected to a 99.99% accuracy rate. Since the test is so accurate, we decide that whenever a crime is committed, we will just have everyone in the area take the lie-detector test, asking them the question "Did you commit the crime?". Clearly, when someone fails the test, they are 99.99% likely to be the criminal. Right?
Except no. In cases like this (where the average person is much much much more likely to NOT be the criminal, the error rate will overwhelm the actual guilty-rate. If we are testing everybody in an area, then we can suppose that each person we check has an average chance of being the criminal of about 1 in however many we are checking. If this number we are checking is very large, then we are CERTAINLY going to have quite a few people who are found to be guilty on the test but are actually innocent. It will pick out more innocent people than guilty people.
While this sort of statistical phenomena will not take place if we don't giving blanket tests to everyone and limit the test to people who we already believe are very likely to have committed the crime, we as a society have a very bad tendency to not understand the statistics and think we should just give everyone the test and let the results tell us who is guilty. If you doubt this, just look at how many people think we should have a DNA database that everyone needs to join (so we can just run any DNA found at a crime scene against it). This combines the birthday paradox with the statistics I described above to create a situation where we have a very real fear of false convictions, exacerbated by the fact that people who are relying on this evidence (juries) do not realize that even a test with 99.999% accuracy can have a very high false positive rate in these sorts of circumstances.
Check out http://en.wikipedia.org/wiki/Bayes'_theorem#Example_1:_Drug_testing for more info on the math behind this.
Citation needed.
"Proof beyond a reasonable doubt" is not a formula or a slogan, to be sold, like Ivory soap, as "99 and 44/100% pure."
It only means, that in the light of all the evidence presented, the jury can in good conscience say that the defendant's guilt has been proven to their satisfaction and that any questions which remain will not alter their decision.