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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

#131

Post by bradknowles »

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…

When I graduated college, my first job was working for what was then the Defense Communication Agency (now Defense Information Systems Agency), in a job that required a successful Secure Background Investigation for a TS/SCI clearance, and I was told that the position required a lifestyle polygraph + random urinalysis.

I used this to my advantage on more than one occasion, when the gaming group I was with was a bit too casual with their use of certain recreational pharmaceuticals. I told them straight out that my job required a lifestyle poly and random urinalysis, and that if they decided to do that to me the next morning, then I would be totally giving up my friends to the examiners. That usually convinced them to be more careful.

Strangely, the government never actually gave me a polygraph or urinalysis test, ever.

Re: Why Lie Detector Tests Can’t Be Trusted

#132

Post by aksss »

riffic wrote: post #6

> Bureaucratic usefulness, rather than any scientific validity, goes a long way toward explaining why the polygraph became a standard instrument of the American national security state. In other words, it's pseudo-scientific bullshit.

meh. it's biometrics. How the data is incorporated into the subjective interrogator's experience and knowledge framework is where the weakness is. But don't blame the robot. IOW, the polygraph is just outputting data, the rigor of applying the data suffers from underdeveloped understanding, but if I were an interrogator I'd much rather have biometric data in my back pocket than not.

Re: Why Lie Detector Tests Can’t Be Trusted

#133

Post by bradknowles »

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…

So, I would have totally failed the test repeatedly, because I would keep insisting on fully explaining the circumstances under which I had heard about the methods but not actively researched them.

And I would tell them to check my shoe and see that there is no thumbtack there. And check my cheek to prove that I'm not biting it in secret. And otherwise expose all the other methods that I know of, and prove that I'm not using any of them.

I'm sure that I would have frustrated the hell out of them, and they would have made damn sure that I always failed the tests, every time.

Re: Why Lie Detector Tests Can’t Be Trusted

#134

Post by aksss »

JackFr wrote: post #58

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.

Oh come on! You're going to drop a book reference but not cite the book?? That's just cruel.

Re: Why Lie Detector Tests Can’t Be Trusted

#135

Post by bradknowles »

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…

When the Secret Service came to interview my grandmother, that's when things got the most interesting for me.

So the story goes, they only did that because the Defense Investigative Service didn't have anyone who could do the job locally, and so DIS must have asked around to find out who could do the job for them. But DIS agents definitely talked to various friends from college and other neighbors I had over the years.

Apparently only my grandparents got the visit from the Secret Service.

Re: Why Lie Detector Tests Can’t Be Trusted

#137

Post by anonymfus »

thfuran wrote: post #100
tempestn wrote: post #87

Earlier quoted context omitted.

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

How is that even supposed to work?

A TV viewer thinks "How about butt clenching?", then one of the characters in the TV show articulates this thought and other gives a response. What actually the response is usually does not matter, because TV viewer already felt some connection with the show when that question was asked.

https://www.youtube.com/watch?v=x8w95xIdH4o

Re: Why Lie Detector Tests Can’t Be Trusted

#138

Post by bradknowles »

mipmap04 wrote: post #109
Causality1 wrote: post #103

Earlier quoted context omitted.

I wonder if you could get prosecuted or investigated for things you admit to during the interview. I also wonder if there's any sort of legal privacy requirement that stops the examiner or someone else with records access from spreading around information related to your examination. I'd warrant most people have gotten away with doing things that should've gotten them arrested.

They do threaten legal action if you lie about something on your SF-86.

Lying about something on your federal forms would make you vulnerable to blackmail, so that would definitely be something that the investigators would try to turn up.

In my case, I was extremely open and honest with the main investigator that I was interviewed by, including the things I did during college with recreational pharmaceuticals. I told all my friends to just "tell the truth" about what they saw happen.

I think my biggest benefit there was telling the story about how I saw that kind of stuff tear lives apart, and turn people who had been best friends into worst enemies, and the negative follow-on impacts of what happens when you can't pay your rent, you can't pay your electric bills, etc... because you have this debt to someone else that suddenly must be repaid this afternoon.

Re: Why Lie Detector Tests Can’t Be Trusted

#139

Post by bradknowles »

throwawy123 wrote: post #82
ghostbrainalpha wrote: post #73

Earlier quoted context omitted.

Forgive me for asking if you are uncomfortable saying, but were they correct about your drug use? I'm coming very close to being 100% eligible for my security clearness but some of those questions would be tricky for me right now. I've often wondered if I could round 8 years up to 10 to pass a polygraph.

Unless you used to have a serious meth or heroine problem I'd say you're fine. ;) I was pretty honest about my drug use. The way they phrase the questions sometimes leaves you with a bit of doubt, though. Like, "How many times did you use this drug?" I'm not sure who keeps a really diligent record of how many times they do drugs at parties. But, yeah, I tried to be as accurate as possible, modulo that doubt about how…

At least when they interviewed me back in 1989, I was as honest with them as I could be about what I could remember, and I was honest with them about how much I couldn't remember.

I have no idea what the rules are now.

Re: Why Lie Detector Tests Can’t Be Trusted

#140

Post by johnfactorial »

jpmattia wrote: post #68
nxpnsv wrote: post #64

Earlier quoted context omitted.

Trying to keep a random number secret likely is less stressful than an actual lie. Even if lie detectors worked this wouldn’t be a great approach. My way is better, scrap them for parts and buy beer for whatever is left over.

> Trying to keep a random number secret likely is less stressful than an actual lie. Which begs the issue: If a lie detector is accurate only for answers that are stressful, then it sure looks like we need a detector to figure out if an answer is stressful or not. Or to put it differently, now you have two problems: Lie detection and stressful-answer detection. Nevertheless, I concede that your beer detection plan is…

Indeed it occurred to me when I took my LDTs that the test's basic premise is: our machine detects stress responses, and our questioner assumes repeated stress coincident with the same answer equates to a lie. Stated outright like that, everyone can see the assumption behind the test is obviously, irredeemably flawed.

Therefore I too must concede that the beer plan is flawless.

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