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Ohio Court Admits Lie Detector Tests As Evidence
An anonymous reader writes "Last month, an Ohio court set a new precedent by allowing polygraph test results to be entered as evidence in a criminal trial. Do lie detectors really belong in the court room? AntiPolygraph.org critiques the polygraph evidence from the this precedential case (Ohio v. Sharma)."
I was thinking about moving to a different State, but hadn't figured out which one. Now I'm down to 49 possibilities.
The higher the technology, the sharper that two-edged sword.
...as long as people are still searching for some magical way to get the truth out of somebody. Won't happen short of the next fifty years of neurological research.
There is no replacement for displacement.
Getting evidence admitted is one thing, but getting a jury to believe it or give it any weight or credibility is something else entirely.
This post expresses my opinion, not that of my employer. And yes, IAAL.
"Do lie detectors really belong in the court room?"
No. Next question please.
Imho, polygraphs should not be used. The simple reason is that some of the more violent and unpleasant people, psychopaths, show blunted responses in psychophysiological tests compared to your 'regular' violent perpetrator. As psychopaths tend to be the ones we should really keep off the streets then a misinformed jury might take polygraph results as definitive evident the perpetrator (psychopath) had not committed the offense and judge accordingly. Also, with a bit of practice and insight, some people are able to control their responses or give misleading results. There's no definitive objective means determining whether someone is telling the truth or not... next to honest evidence the polygraph is pretty useless. It's a nice idea but anyone who has used these psychophysiological tests will know, for every half decent result you also get a fair bit of noise (excluding, of course, the people ho make and sell polygraph tests).
I remember seeing a clip of Groucho being subjected to a polygraph from the 50s, and while funny, it didn't inspire any sort of confidence in the technology.
I agree, that considering how many minor things are consider to taint the jury, a polygraph is probably just about the worst of them. The reliability just isn't there, and even when they are accurate, they don't really give any indication of what the lie actually is.
Worse, they tend to work worse when the subject is already under stress. Overall, the technology just isn't there, and won't ever get there. If anything is more reliable, it'll be of a different form, probably something that scans the brain directly. Even that though is going to be tough.
The most common figure for the accuracy of polygraph tests is 70%. Which sounds reasonable, until you realise that since the situation is binomal -- i.e. the only possible results are "truth" and "lie", so pure chance (e.g. flipping a coin) would give you 50% accuracy; at which point 70% starts to look considerably less impressive.
As I understand it, the most useful (from the police's point of view) way to use of lie detectors is psychological: pretend that they're 100% accurate, get the suspect to say "I didn't do it", bluff and claim that "The Machine Knows You're Lying", and get them to give a confession that way. Of course, such a strategy will fail if the polygraph becomes so widely used that everyone becomes familiar with its limitations.
What's purple and commutes? An Abelian grape.
Professional polygraphers will claim their test works 96% of the time. Those claims are bald-faced lies. Regardless of that we can take a look at what happens if the test really did work 96% of the time.
Some employers have been known to hire polygraphers to identify which employee may have been involved in some inside theft (or similar situation). The employer asks the polygrapher to test 50 employees. The odds that the tests will be correct with all 50 employees is 0.96^50=13%. So there is an 87% chance the test will accuse an innocent person...and that assumes the test is correct 96% of the time. What invariably happens is the polygrapher 'discovers' the culprit after the first few tests, packs up his things, and goes home. He identifies the suspect so quickly because the test is only right 65% of the time. Whether the accuracy is 65% of 96% the test will still point to a suspect even if none of the employees did anything wrong.
I once interviewed for a job and was told that I would be required to handwrite a statement so it could be analyzed by their "handwriting expert." I promptly got up and left. They looked shocked. Apparently they initially tried polygraphing applicants, but found it to be too expensive. Years later I bumped into the HR person at another job and asked her about the success of the vetting process. She said it didn't work and if anything made things worse.
Man will never be free until the last king is strangled with the entrails of the last priest. --Denis Diderot
It doesn't "detect lies"!!! It detects physiological changes ONLY! Determining what those changes actually mean is entirely subjective and open to varied interpretations!
You're using her as bait, Master!
In this case it is the DEFENSE offering the lie-detector evidence. Most sexual molestation/battery cases come down to he-said she-said. Lots of innocent people have been convicted under these circumstances. While lie-detectors are not perfect I think in this type of situation they are perhaps appropriate. I would not allow them for prosecution (which is what I think a lot of knee-jerk post here have assumed) and only in cases where the evidence comes down to what is being said by two people, which appears to be what the Judge has decided in this case. While lie-detectors are only about 70% accurate, that is better odds than deciding just on the demeanor of two people in court.
I can sympathize that women are outraged by the high number of men that get off scott-free with these type of charges, but that doesn't alter the fact that it really isn't fair to convict someone on nothing more than an accusation by one person without direct supporting evidence (bruises are not direct evidence). Yes direct evidence is hard to come by in these cases, they are usually executed in private without other witnesses, but I for one would rather see 10 guilty men free than send 1 innocent man to jail.
Letter To Iran
There was a wired article on fMRI lie detectors.