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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

#171

Post by myrandomcomment »

throwawy123 wrote: post #36

I took a polygraph twice for an NSA internship (TS/CSI Clearance). It's an interesting process. In the first phase, you go over your security forms (SF-86 and related) in detail with your polygraph examiner. They ask a lot of detailed questions, sometimes including things you aren't legally required to disclose (drug use and foreign travel outside the listed time limits). In the second phase, they hook you up to the…

The key is just to answer honestly no matter what the question. Did you have sexy with a goat? If the answer yes, then say yes. They do not care. What they care about is you tell the truth with no reservation as it a sign you cannot be blackmailed.

Re: Why Lie Detector Tests Can’t Be Trusted

#172

Post by giles_corey »

rndgermandude wrote: post #25
taxidump wrote: post #18

I passed a polygraph, I was untruthful and still passed. The person administering the test had done tbis for the FBI for 15 years. I had no special training.

Ye, well, e.g. Ted Bundy passed a polygraph. And the Green River Killer did too. But hey, another dude, innocent of course, did not pass the lie detector when they were looking for the Green River Killer. Oops

To the best of my knowledge, Ted Bundy was never polygraphed. You are correct about the Green River Killer (Gary Leon Ridgway) and the innocent man (Melvin Foster):

https://antipolygraph.org/cgi-bin/forums/YaBB.pl?num=1067927...

Re: Why Lie Detector Tests Can’t Be Trusted

#173

Post by giles_corey »

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.

The 1998 Employee Polygraph Protection Act largely prohibited the use of lie detectors for employee screening by private companies.

Re: Why Lie Detector Tests Can’t Be Trusted

#174

Post by giles_corey »

tempestn wrote: post #87
Spearchucker wrote: post #71

I've done a few and never failed one. Was told to clench my butt cheeks really hard to get a pass. Another tip was to put a drawing pin into your shoe and push down onto it with your foot as hard s you were able to tolerate. And if you search online there are a few other techniques you can use to ace the tests. Most interesting for me was being told I'd failed a test I was later told I'd passed. It's sheer madness.

At least on TV there are now pressure sensors in the seats to catch the butt-clenching thing.

For federal agencies, the seat pad is now standard. There are no public studies of its effectiveness. Regarding how the U.S. government attempts to detect polygraph countermeasures, see:

https://antipolygraph.org/blog/2018/06/09/ncca-polygraph-cou...

Re: Why Lie Detector Tests Can’t Be Trusted

#175

Post by daveFNbuck »

blackflame7000 wrote: post #142
derivagral wrote: post #107

Earlier quoted context omitted.

Sadly (and incredibly) this is not always true: https://en.wikipedia.org/wiki/ADE_651

"as much as US$60,000 each. The Iraqi government is said to have spent £52 million on the devices" - Wow and no one thought hey let's test this baby out before we buy a thousand of them?

They did test them. Dowsing rods work very well in unblinded tests. That's a big part of why so many people believe in dowsing.

Re: Why Lie Detector Tests Can’t Be Trusted

#176

Post by lovemenot »

pmarreck wrote: post #93
oufoufouf wrote: post #79

The dumbest things about these polygraphs is that you're pretty much forced to lie if you want to pass. Some of the questions were vague and if you are a normal human being without a halo glowing on your head you would fail. Questions like "Do you love your parents?", "Have you ever spread gossip?", "Have you ever done anything immoral" (My interviewer specified watching pornography as something immoral). Thankfully…

> watching pornography as something immoral Well, there goes everyone.

I don't agree with this rebuttal. Though it happens a lot, people often assume wrongly that everyone uses pornography. No doubt many do, and good luck to them.

But there is no need to make a majority into a universal here.

Re: Why Lie Detector Tests Can’t Be Trusted

#177

Post by stephen_g »

myrandomcomment wrote: post #171
throwawy123 wrote: post #36

I took a polygraph twice for an NSA internship (TS/CSI Clearance). It's an interesting process. In the first phase, you go over your security forms (SF-86 and related) in detail with your polygraph examiner. They ask a lot of detailed questions, sometimes including things you aren't legally required to disclose (drug use and foreign travel outside the listed time limits). In the second phase, they hook you up to the…

The key is just to answer honestly no matter what the question. Did you have sexy with a goat? If the answer yes, then say yes. They do not care. What they care about is you tell the truth with no reservation as it a sign you cannot be blackmailed.

The polygraph can't actually measure anything that can (with any reliability) indicate whether you're telling the truth or lying though. It's basically just a prop to try and stress the subject out and convince them that the examiner can tell what they're thinking. The examiner (really interrogator, calling it a "test" is too generous) will literally pick random things that they feel you're being evasive about and drill you on it, even if it has no relation to the truth!

Re: Why Lie Detector Tests Can’t Be Trusted

#179

Post by jobigoud »

hestipod wrote: post #126
Spearchucker wrote: post #71

I've done a few and never failed one. Was told to clench my butt cheeks really hard to get a pass. Another tip was to put a drawing pin into your shoe and push down onto it with your foot as hard s you were able to tolerate. And if you search online there are a few other techniques you can use to ace the tests. Most interesting for me was being told I'd failed a test I was later told I'd passed. It's sheer madness.

They often ask you explicitly if you know or have researched methods to defeat the polygraph. It's a lose/lose situation because most people have heard of such things or DID research out of curiosity facing taking a test, but admitting it makes you look bad. You generally don't get the chance to explain yourself, and if you do it just makes you look more guilty. The entire process is designed to give an excuse to arr…

Q: Are you capable of defeating this test?

A: No.

The answer does not convey any information whatsoever.

Re: Why Lie Detector Tests Can’t Be Trusted

#180

Post by [deleted] »

jldugger wrote: post #162
zacharycohn wrote: post #101

Earlier quoted context omitted.

The parent poster is correct. This is a standard practice for polygraph interviews. The pick one question, more or less at random, and double/triple/quadruple down on it until you break. Or don't. I got "have you ever committed a crime" (and after a actually pretty cool conversation about filesharing vs recording songs off the radio with a tape recorder, I passed). A friend of mine got "have you ever had sex with ani…

Sadly, 'Fuck you and the horse you rode in on' would be an inappropriate response.

[deleted]
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