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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.
Nice tech, but it's not there yet.
What happens to the right to remain silent when it is there? The British have already gutted this right. Not that hard to envision the same happening here.....
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
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. It seems to me one of those is far more likely to improve than the other and I'm not talking about Homo Sapien's ability to use critical thinking skills when confronted with conflicting emotive/subjective versions of events.
Also it is would only be a portion of the evidence which the case depends upon currently for it to reach a verdict. Anyone who compares this to lie detector machines does not understand that lie detectors are little better than a coin toss. This when properly used has been shown to top out at 90%.
An Education is the Font of All Liberty
But of course the whole point is that facts, taken in total, tend to point the way to the larger truth at issue. How else would you have us do it?
caritj.org
It's a lie detector not a mind reader.
Yeah! Do you know how expensive it is getting Kreskin to testify? Plus, I bet he's booked for months in advance.
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."
I mean come on, fMRI has even been used to definitively prove that dead fish can think! (http://neuroskeptic.blogspot.com/2009/09/fmri-gets-slap-in-face-with-dead-fish.html) How much more scientific proof for its accuracy do you need?
The only thing necessary for evil to triumph is for it to be pitted against a slightly greater evil
I wouldn't be sure to trust this brain energy pattern recognition for a verdict- as far as I am concerned, it is much better to cut loose someone that _might_ be guilty, than to convict someone that is not.
The three laws of thermodynamics:(1) You can't win. (2) You can't break even. (3) You can't even quit.
http://dsc.discovery.com/fansites/mythbusters/db/human-body/beat-lie-detection-test.html
This is a huge victory for humanity. What it really means is that the machines cannot tell when we're lying.
What you say would be correct if people were being convicted only on the basis of this fMRI lie detector test. In practice, how you get to a 1/1000 error rate is by combining several less reliable sources. For example, convicting somebody on the basis of one witness is crazy, but convicting them on the basis of 10 witnesses is reasonable. (Given certain assertions of statistical independence etc).
http://www.wired.com/wiredscience/2009/09/fmrisalmon/
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".
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."
A fMRI is not a lie detector test it is more of a memory test, so unless the criminal is delusional or has those morphological differences I mentioned in my first post he is not going to get off.
An Education is the Font of All Liberty
Here is the interesting hypothetical:
Assume this lie-detector is right 80% of the time, and that its success/failures are randomly distributed (e.g. not associated with socio-economic background).
Assume also that false conviction rates are at 21% (so only 79% of convictions are correct), and that there is substantial evidence that this is not evenly distributed (e.g. that false convictions are associated with low socio-economic status).
Would you be willing to entirely replace the system of jury trials with trial by lie detector?
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.
Without proper correction, fMRI has been shown to detect brain activity in a dead fish. Next up, trial lawyers.
Learning HOW to think is more important than learning WHAT to think.
Grant beat it by doing complex math in his head while they asked him questions. Couldn't find a video, but found summary.
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".
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). /., 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).
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
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.
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
Interestingly, just a few days back the Supreme Court of India banned any forced polygraph/Narco/Brain Mapping Tests as they violate the constitution as well as the privacy of a citizen, are essentially asking a person to testify against himself, are as bad as torture, and are no better than getting a person drunk .