Discussion in 'Ethics, Morality, & Justice' started by Orleander, Jan 13, 2013.
Why can't the results of a lie detector test be used in court?
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heart problems and various mental attitudes makes them unreliable
Because you can cheat it.
here are instructions: http://www.wikihow.com/Cheat-a-Polygraph-Test-(Lie-Detector)
then why would they ask anyone to take one and why would anyone agree to do so? Its not scientifically accurate and its results could weigh against you in public opinion
They do not ask you take the exam, you must ask for it to be given but remember those machines can screw up both ways so be careful that you don't get a bad machine that says your lying when your not.
I'm under the impression that the cops ask you to take one. You don't have to if you don't want to, but they let everyone know you refused
Refusal to take a Lie detector test also disqualifies for a job if it is required there, as for police questioning, it can be used as support for incrimination.
Then your under the wrong impression and should change your way of thinking about this subject. Would you like a link to show you the police do not ask for you to take polygraph tests?
Sociopaths can beat a lie detector just about every time. To make one work you must have an emotional response that can be measured by your physical responses such as breathing, perspiring, heart rate...etc.
Yes it is a tool they can use to help them find a suspect they can focus more attention on. If they are asking you to take one. Politely decline and ask for a lawyer as you need legal advice right away. At this point if they haven't already they might arrest you, but that's far better than you blundering around in your ignorance of the law. Remember the cops can lie to you in the hope of tripping you up in some way.
the fact that its not scientifically valid is an interesting point given the report by the US Academy of Science that with the exception of DNA (which comes from medical science rather than the justice system) virtually no forensic "science" stands up to scientific standeds or has been tested to scientific standeds. For instance fingerprint anlylisis which in spite of the "experts" argument was shown to be fatally flawed during the Madrid bombing case
The problem with fingerprints is that not all forensics labs use the same standards to make their determinations as to who they belong to. Next, most people don't have their fingerprints in the national or even local databases. So unless you can catch the guilty party to compare prints with your just SOL.
DNA testing has its faults too...Josiah Sutton for example was accused of rape, a crime he did not commit.
and now think of the thousand of innocent men who are in jail thanks to the "foolproof" DNA testing, for whom no one cares.
No such body of prisoners exists. The link you posted is to a group that uses DNA testing to free innocents wrongly convicted - they use it because it is far more reliable than any other form of evidence, and can be used to contradict even an overwhelming body of other kinds of evidence.
Lie detector tests are too easy to manipulate, as well as fool, to be admitted as evidence. They are used mostly to intimidate people - scare them into talking. (Somewhere, probably on the internet by now, there is a documented case of police using rigged up headgear and a copy machine set to print out "He's lying" whenever started, to extract a confession from a less than clever suspect. The real thing is not much different, in practice).
One of the main reasons polygraphs are not admissible is because the accused has a Constitutional right to confront the evidence before him. However, in a polygraph there is no actual evidence. There's some ambiguous data and a report by a polygraph examiner giving his opinion that you lied. It amounts to hearsay.
Unfortunately the polygraph does get used outside of court in ways that can hurt innocent people. There probably could be a way to put a stop to it, but it would be a huge legal undertaking; for example, someone might raise a claim of violation of their civil rights, possibly under the Due Process Clause. But it would cost a fortune, and either get summarily thrown out, or else languish in the courts for a decade or more before settling without a decision.
This comes up from time to time in legal venues, but it's way, way behind the priorities of the people who are always grabbing the spotlight on national priorities. It will probably remain one of a hundred or so legal issues that are messing people up every day, but which are left unresolved.
ummm no actually its not, firstly there is no impartial method of fingerprint identification, computers DON'T make matches, people do. This leads to a situation where you can get cognitive bias, was trying to find the study done where by a researcher changed the details of cases where a certain fingerprint match was made, and then sent those same fingerprints back to the SAME examiner and the result was that in 50% of cases the examiner said there was no match. Fingerprints have been argued to be 100% certain, that no one has the same fingerprint as you but there has never been a study to prove this and along comes the Madrid bombings where 3 fingerprint experts in the FBI including the head of there fingerprint division found that this fingerprint was a match to this guy and then the defenses OWN independent fingerprint examiner agreed with them and they were ALL WRONG. 2 people DO have fingerprints alike enough to be mistaken for each other. This is likely not the only time, its just the only time there has been conclusive proof that finger print identification was plain wrong. Not bad operators, bad "Science"
Lie detectors are pseudoscientific voodoo. Countless scientific studies at universities have shown them to not work very well (although there is no shortage of people who make money from them, and not surprisingly those people tend to claim that they work super). Simply search for "polygraph review" in google scholar for plenty of references.
They are only really useful for intimidating gulible people; if you hook someone up to a fancy-looking machine and tell them "If you lie to us, WE WILL KNOW IT!!!" there's a chance they might believe you and tell the truth when they would otherwise have lied. Often the "test" involve all sorts of elaborate theatrics to convince the subject that the test is accurate and scientific, like asking prelininary questions to "get baseline readings," etc. This has more to do with tricking the subject than anything else.
There are many mythical "tricks" for beating lie detectors, but most of them have more to do with simply giving the subject confidence that they won't get caught than with actually messing with the polygraph data; if the subject is confident that the lie detector won't work, then it won't work.
Fun fact: many of the most damaging spies in modern US history either passed polygraphs, of failed polygraphs but had the failure ignored because the investigators who performed the test were well aware that the test wasn't reliable. When Aldrich Ames went to his Russian handlers in a panic because he learned he would have to take a lie detector test, they laughed and told him "Just lie..." He passed the test, and was only caught later because he was spending far more money than his salary would have allowed.
No, the polygraph isn't admissible because it fails to pass the Daubert Standard, a rule that say such evidence can't be admitted if it's not generally accepted by science as valid and accurate. If actual scientists (rather than just the people who make money selling polygraphs) ever reached a consensus that polygraphs actually worked, they could be admitted as evidence in the same way as any other forensic evidence. But, as discussed above, most scientists agree that lie detectors are pseudoscientific bullshit.
The guy who created the first Polygraph test machine, William Marston, also created the Personal Profile System DiSC.
The difference between DiSC and Myers Briggs Personality Type Indicators is that the former is based on surface traits while the latter is based on core traits.
The other main difference, comparing post 1994 DiSC to pre 1994 DiSC, is that the classifications for people who ticked all of the best choices or all of the worst choices were dropped.
In Olympic gymnastics the highest and lowest scores are discarded to avoid bias. Why would you ever expect anybody who identifies themselves as either absolutely good or absolutely bad to be expressing a core trait or an honest self assessment? The old pre 1994 DiSC surface trait test identifies these people because they tick all of the ones OR all of the zeroes. This is a simple binary test that does not rely on a machine and it does explain a lot of things.
Too bad a real lie detector couldn't be perfected. It would stop a lot of innocent people going to jail and remove the need for Judges and lawyers, as I am convinced the entire legal system is pretty screwed up. It would be even better if they had roadside units.
Could it ever be possible? Who knows. As long as the brain can forget incidents and replace memories then not likely.
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