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Why Lie Detector Tests Can’t Be Trusted

smithsonianmag.com

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Re: Why Lie Detector Tests Can’t Be Trusted

#51

Post by taftster »

TomMckenny wrote: post #32
taftster wrote: post #11

Earlier quoted context omitted.

Some polygraph setups will include a "butt pad" that you sit on that can detect your flinching. I think it's interesting because it somewhat supports the claim. If clinching didn't work or help in some way, why bother including a motion detector under your backside.

Those who believe clinching works also believe polygraphs work (except when clinching) Remove the clinching illusion and you restore the polygraph illusion to that group.

Right. I don't honestly understand any justification for the "defenses" described (at various websites). If the polygraph just doesn't work, why attempt any "countermeasures". The whole thing is kind of funny.

I think you're exactly right. The fact that the "butt pad" is there means that you have to believe that clinching would have any effect one way or the other. So the butt pad is really just part of the overage mirage.

Re: Why Lie Detector Tests Can’t Be Trusted

#52

Post by jdoliner »

glitchc wrote: post #2

Lie detector tests rely on psychological intimidation. The testee invariably gives up compromising information over the course of the test, allowing the tester to apply leverage or outright coercion. If no useful information is divulged, the test is marked a fail and requires a repeat.

There's a wonderful scene in The Wire where they give a young thug a "polygraph test" by interviewing him in front of a copy machine and hit the copy button when he answers a question so that it spits out the message they preloaded into the machine "false." The thug looks crestfallen and tells them the truth.

Re: Why Lie Detector Tests Can’t Be Trusted

#53

Post by the-pigeon »

throwaway66666 wrote: post #42
komali2 wrote: post #35

Earlier quoted context omitted.

Why were you taking a polygraph? Just curious.

Some jobs require it. Not even super-secret top-hacker men-behind-the-curtain type of operations. If you wanna be a senior sys admin for bed bath and beyond, you 'll be probably getting one.

Wow. Never heard of a non-government agency using them.

Pretty clear sign of a messed up company culture.

Re: Why Lie Detector Tests Can’t Be Trusted

#54

Post by bityard »

khawkins wrote: post #34

There's a lot of hyperbolic claims being made in the article and these comments which seem unsupported by science. The answer to the question, "can polygraphs be utilized to draw out truth?", is a resounding yes: >Notwithstanding the limitations of the quality of the empirical research and the limited ability to generalize to real-world settings, we conclude that in populations of examinees such as those represented…

> Although it is not a silver bullet, it certainly has its applications, especially if the person being interviewed believes it works.

The whole premise of a lie-detector test is that they are marketed to end user and the public at large as being both accurate and "scientific." That they yield results better than chance isn't particularly relevant: they are not what the sellers and users of them claim they are. The conclusions drawn from the readings of the machines are only loosely based on anything scientific and depend heavily on the interviewer's own personal biases. Yet they determine the fate of people's lives all the time.

Re: Why Lie Detector Tests Can’t Be Trusted

#55

Post by the-pigeon »

Diederich wrote: post #47
throwaway66666 wrote: post #42

Earlier quoted context omitted.

Some jobs require it. Not even super-secret top-hacker men-behind-the-curtain type of operations. If you wanna be a senior sys admin for bed bath and beyond, you 'll be probably getting one.

> If you wanna be a senior sys admin for bed bath and beyond, you 'll be probably getting one. Huh. I was a very senior 'sys admin' type for an enormous retailer for over a decade, and polygraphs never came up for me or anyone else there. Any idea why bed bath and beyond is into such a thing?

My guess would be. Some sys admin did something illegal (some sort of fraud or something). So management wanted changes to prevent that in the future. And the cover your ass move was "we'll use polygraphs on new people!".

Re: Why Lie Detector Tests Can’t Be Trusted

#57

Post by the-pigeon »

goatlover wrote: post #16
yholio wrote: post #8

Earlier quoted context omitted.

The polygraph is entirely scientific in the way it actually works: eliciting forced confessions under psychological coercion. However, for that coercion to be effective, the targets and the public at large must be convinced of a pseudoscientific idea that lies are detectable physiologically. Hence the conflict between the promoters and the detractors, proving that it works would make it no longer work.

And how do we know whether a forced confession is true? False confessions do happen under other circumstances. Obviously, if the subject reveals something backed by evidence they wouldn't have known being innocent, that's one thing. But if we're using their confession as the evidence, then it's the same problem as any forced confession.

Not at all.

Any information you receive verbally from a single source is not very reliable regardless of how it was obtained.

Re: Why Lie Detector Tests Can’t Be Trusted

#58

Post by JackFr »

I passed my NSA polygraph, though it was uncomfortable. However my psych interviewer was able to get disqualifying info out of me using just technique.

It was only years later while reading a book about the Shin Bet (Israeli military intelligence), I recognized the way I was manipulated.

No hard feelings, after all I was telling the truth, and I probably would have hated the job anyway.

Re: Why Lie Detector Tests Can’t Be Trusted

#59

Post by hansjorg »

taftster wrote: post #23
glitchc wrote: post #2

Lie detector tests rely on psychological intimidation. The testee invariably gives up compromising information over the course of the test, allowing the tester to apply leverage or outright coercion. If no useful information is divulged, the test is marked a fail and requires a repeat.

Yes, exactly. Polygraphs are just a form of interrogation technique, disguised as "science". If the science was debunked, then the credibility of the machines would be questioned and the interrogation process would not yield as positive (if you can call it that) results. So the whole mystique of polygraphs must be guarded to keep up the facade of the lie detector's true capabilities.

It's a good example of black magic.

Re: Why Lie Detector Tests Can’t Be Trusted

#60

Post by excalibur »

Diederich wrote: post #47
throwaway66666 wrote: post #42

Earlier quoted context omitted.

Some jobs require it. Not even super-secret top-hacker men-behind-the-curtain type of operations. If you wanna be a senior sys admin for bed bath and beyond, you 'll be probably getting one.

> If you wanna be a senior sys admin for bed bath and beyond, you 'll be probably getting one. Huh. I was a very senior 'sys admin' type for an enormous retailer for over a decade, and polygraphs never came up for me or anyone else there. Any idea why bed bath and beyond is into such a thing?

My guess is that throwaway's statement was hyperbole, and Bed Bath and Beyond isn't a literal example of an employer that requires a polygraph. Instead it was an exaggeration meant to show how common the practice is in his circles.
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