Why Lie Detector Tests Can’t Be Trusted

https://www.smithsonianmag.com/innovation/why-lie-detector-tests-cant-be-trusted-180972724/

by pseudolus • 7 years ago

272 190 7 years ago

glitchc• 7 years ago

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.

pixelbath• 7 years ago

In my experience, that's not how the session goes. All the questions are reviewed in advance with the interviewee; there are no surprise questions. The interviewer I worked with even mentioned which questions he wanted and expected lies to. Many of these were somewhat personal questions ("Do you live at X; Is your mother's name Y?"), but nothing overly invasive.

Granted, I did not participate in any polygraph sessions used for the purposes of information gathering; more to confirm information already in the open.

hirundo2• 7 years ago

I had the "intimidation" kind of polygraph session when I was questioned by a couple of police detectives about a theft in a building where I was a security guard. Intimidation and threats. Like if you don't answer right we're headed to your place to search everything. They did not review the questions in advance; they did try to surprise me; there was no attempt at calibration. The lie detector seemed to be a prop. After the test one of them came to me and said "you passed" while looking at me closely like my reaction was just the last test. I laughed. I guess it was the right answer.

taftster4• 7 years ago

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.

the-pigeon4• 7 years ago

I mean they have been debunked and anyone that Google's it knows it.

Doesn't mean they don't work as an intimidation tactic. Though most of the agencies that use them are probably filtering out a lot of good employees by putting them through a test designed to mess with them. Instead of focusing on whether the person has the skills needed for the job.

hansjorg• 7 years ago

It's a good example of black magic.

LocalH• 7 years ago

Even the name "lie detector" is a misnomer, polygraphs have absolutely nothing to do with "detecting lies". They just detect physiological changes during a line of questioning.

jdoliner• 7 years ago

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.

stevekemp• 7 years ago

For reference this is the scene:

https://www.youtube.com/watch?v=AJ5aIvjNgao

gmoore• 7 years ago

There is a lot of great info on the subject at https://antipolygraph.org/

pseudolus2• 7 years ago

The site offers a >200 page free PDF that details the failings of polygraph testing and lists extensive countermeasures [0].

[0] https://antipolygraph.org/lie-behind-the-lie-detector.pdf

pseudolus2• 7 years ago

Not quite a pseudoscience but not so accurate as to warrant allowing a person's life to be upended as has been documented on many occasions [0]. Unsurprisingly, there's a history of the polygraph industry litigating against third parties that question the reliability of polygraphs [1].

[0] https://www.wired.com/story/inside-polygraph-job-screening-b...

[1] https://antipolygraph.org/

yholio• 7 years ago

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.

goatlover2• 7 years ago

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.

yakshaving_jgt• 7 years ago

tl;dr (and I don't think it's even mentioned in the article)

You can cheat a polygraph by flexing your anal sphincter.

More: https://www.youtube.com/watch?v=NsoI92BfmqY

rolltiide3• 7 years ago

You just need to show consistency

Imagining that I’m running gets my heart rate up, I can keep my breathing consistent, and the finest sensor detects perspiration changes on your finger which is the toughest but also a mental game.

Finally you need to consider the psychology of the tester or institution testing you. There are irrelevant questions that may not be yes or no questions, but its often more important for you to not be a free thinking paralegal expert and instead a soldier that complies.

So if the question is “have you illegal downloaded mp3s” the answer isn't “the consumer doesnt have the burden of knowing if the provider owns the copyright or associated license and copyright infringement only occurs if you share it” its just “no”, but if you can rationalize your compliance with the legal defense then it will be seamless to say “no” without showing an anomaly on the polygraph

Also congratulations you're a sociopath now, just focus on your breathing

jandrese3• 7 years ago

Some questions will cause some people to panic regardless. "Have you ever had sexual thoughts about underage people? Yes or No."

taftster4• 7 years ago

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.

TomMckenny• 7 years ago

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.

riffic• 7 years ago

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.

aksss5• 7 years ago

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.

VikingCoder• 7 years ago

I hold out hope for (f)MRI.

PascLeRasc• 7 years ago

There's some research into guilt measurement with fMRI [1] but it's very hard to test. When my lab tests fMRI thought identification, we need participants to write down exactly what they plan to think about for certain concepts (death, family, etc) and we need them to think about one particular strong memory multiple times. We know, or at least we believe we know, and the participant knows that we know, what they're thinking about. Anything else makes it hard/impossible to classify and won't be accepted in the literature.

Asking someone to pretend to lie in a lab environment, like say responding to "What's your name?" with the wrong answer on purpose, won't elicit the kind of arousal response we want to record like "Did you steal this car?". There's just not a good way to standardize and measure this kind of response without deceiving the participant - you might do some kind of social research on them and ask them questions they aren't prepared for, but understandably no IRB would allow that.

[1] https://academic.oup.com/cercor/article/13/8/830/328813

opwieurposiu• 7 years ago

A problem with fMRI is that most of the software is crap, thus rendering the analysis unreliable.

https://blogs.scientificamerican.com/scicurious-brain/ignobe...

gus_massa• 7 years ago

fMRI still has false positives https://blogs.scientificamerican.com/scicurious-brain/ignobe...

mgamache• 7 years ago

I think part of the issue is that errors are not evenly distributed. There are many more false positives (detecting a lie when the subject is truthful) then false negatives. Most people assume errors are random, in this case they are not. Of course, this is combined with the other unreliability of the measurements make it close to a waste of time.

[https://www.psychologytoday.com/us/blog/the-human-beast/2013...]

hanoz• 7 years ago

Surely everyone knows first hand how much variation there is in the inner experience of telling a lie to realise that these tests are a sham.

boomboomsubban• 7 years ago

I'm fairly sure that you are required to take a lie detector to join the FBI, which makes me worry about the validity of all federal forensics. And now we're resuming executions...

rndgermandude3• 7 years ago

If you're concerned about this, you really shouldn't read up on the actual "forensics" the FBI did in the past, like "hair analysis", because it will ruin your day:

https://www.fbi.gov/news/pressrel/press-releases/fbi-testimo...

Or "bite mark analysis" (don't google that, it will ruin your day as well).

RankingMember• 7 years ago

Is there a proper response to this other than just banging your head against a desktop until you're blissfully unconscious? I can't think of any other response that would properly articulate my response to skimming that article.

c3534l• 7 years ago

You should worry. Nearly the entire field of criminology is pseudoscience. Few techniques employed during the 20th century have stood up to scientific investigation which is because they were never developed scientifically in the first place. It's simply a veneer of science promulgated by those who haven't actually understood the scientific method.

taxidump• 7 years ago

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.

dripton• 7 years ago

I failed a polygraph. I was truthful and still failed. It cost me a job. Luckily I found a better job. So, thanks polygraph.

hestipod2• 7 years ago

I have known multiple people who went through investigations including polygraphs for clearances. They were all told to be 100% honest and that it wasn't violations (within reason) that would hurt them...its not displaying "integrity". Those people were screened out for admitting to minor things like marijuana use etc. One's rejection read like some self righteous admonishment and said something like "You do not display the moral quality of character we here at <insert place> are looking for. We wish you the best in your future endeavors". They were told they failed the polygraph when they were being honest. Frankly if this is the hypocritical "quality of character" those places exhibit...people are better off avoiding them. The agencies/companies prove with their behavior they do not have the honesty and integrity they claim to look for and use these tools selectively. They reward lying and manipulating the system and punish honesty.

rndgermandude3• 7 years ago

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

blaser-waffle• 7 years ago

ALdrich Ames passed a couple of polygraphs.

They only got him because other sources implicated him, and because his finances were notably out of whack for a government employee.

https://en.wikipedia.org/wiki/Aldrich_Ames

jandrese3• 7 years ago

I've heard that they're not very useful with true sociopaths because they require you to be uncomfortable with lying.

giles_corey4• 7 years ago

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...

komali2• 7 years ago

Why were you taking a polygraph? Just curious.

wyxuan• 7 years ago

Lots of gov't jobs require them for dealing with confidential info.

throwaway666662• 7 years ago

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.

m463• 7 years ago

A friend failed a polygraph. She handled money in a resturant and was a scrupulously honest person. She had a genetic health condition and it was probably responsible.

But they knew her character, and even though she didn't pass she didn't have any problem or lose her job.

JTbane• 7 years ago

George Costanza: It's not a lie if you believe it.

leakybit• 7 years ago

The usefulness of the polygraph is not to detect lies, but is to be used as a enhanced interrogation tool.

thatgerhard• 7 years ago

I see a lawsuit coming..

cracauer• 7 years ago

They write an article on polygraphs and do not mention Aldrich Ames?

WTF, NYT?

khawkins2• 7 years ago

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 in the polygraph research literature, untrained in countermeasures, specific-incident polygraph tests can discriminate lying from truth telling at rates well above chance, though well below perfection.

https://www.nap.edu/read/10420/chapter/2#4

Although it is not a silver bullet, it certainly has its applications, especially if the person being interviewed believes it works. Thus, the polygraph test makes sense in questioning sex offenders, for example:

https://onlinelibrary.wiley.com/doi/abs/10.1348/135532508X29...

bityard• 7 years ago

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.

khawkins2• 7 years ago

Most science isn't accurate, that's why it's filled with p-values. They're often only reporting the mere hint of an effect which allows them to distinguish between a control and experimental population.

Polygraphs are almost certainly not reliable enough to convict someone on, but it's not admissible in court. That doesn't mean it can't be used to help coerce a confession or help lead an investigation. And the fact that you won't face up to the extraordinary amount of evidence showing that it can be useful suggests stubborn ignorance on your behalf.

RHSeeger• 7 years ago

What is the use case for a test that can indicate that something is probably the truth or probably a lie when focused on specific incidents? _(According to the study, the reliability drops when used for screening)_

autoexec• 7 years ago

The answer to the question, "can polygraphs be utilized to draw out truth?", is a resounding yes

So can tarot cards, and magic 8 balls. polygraphs are bullshit pseudoscience and 100% interchangeable with any other fake bullshit when combined with a experienced examiner and an ignorant/gullible interviewee

maxheadroom2• 7 years ago

...but isn't the answer to the question, "Can the polygraph be used to coerce false confessions from innocent people?" also quite a resounding, "yes"[0]?

Glossing over or attempting to detract from the grossly negative consequences doesn't automatically arrive at the conclusion that it's resultantly a "good" thing.

[0] https://www.innocenceproject.org/polygraph-tests-contribute-...

throwawy1235• 7 years ago

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 polygraph and ask two series of very specific questions, one called "lifestyle" and one called "national security." Lifestyle questions include questions about drug use, possible crimes, etc., and national security questions include questions about foreign contacts, involvement in terrorism, etc. They're very specific, like "Are you withholding any information about your involvement with illegal drugs in the past ten years?"

About half the time (based on my discussions with other prospective interns), the examiner becomes convinced you're lying about one of these questions and really drills into you. Most of the polygraph examiners are past FBI or CIA interrogators, so they know how to make you very uncomfortable.

I was explicitly told that I failed my first polygraph (the examiner was convinced I used more drugs than I let on), but some of the other interns were drilled about crazier things, like contacts with foreign governments or involvement with terrorist groups.

If you're particularly desirable to the managers who're looking to hire you, they'll keep inviting you to take more polygraphs, and you'll eventually pass.

I ended up turning down the NSA internship for better opportunities after realizing that NSA folks are not the most fun people in the world to hang out with.

teddyh2• 7 years ago

the examiner was convinced I used more drugs than I let on

No they weren’t. They merely pretended they were convinced. It’s all part of the act to make you nervous.

hutzlibu• 7 years ago

Possible, but how can you know for sure, if you were not there?

ghostbrainalpha• 7 years ago

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.

Tushon• 7 years ago

As far as I've heard, it is more about lying than past use (unless that past is a month ago and was a real bender). Telling them the truth about something that happened 9 years ago isn't likely to get you booted.

throwawy1235• 7 years ago

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 possible it is to accurately answer these questions.

everdrive2• 7 years ago

Just don't be inconsistent.

tdfx2• 7 years ago

Depends on the position. For defense and intelligence agencies, they want to see that there's nothing "recent" (past few years) or "chronic" (borderline or outright addictive behavior). If you smoked pot or did cocaine 8 years ago very infrequently you should have no issues.

HOWEVER: law enforcement agencies are quite a different story and tend to be much stricter in their requirements. Some, like the FBI, have public drug qualifier policies you will need to meet [1] and there is no wiggle room (1 day short of 10 years and you're 100% ineligible). Some agencies do not publish this policy (i.e. Secret Service) and you have to guess whether you're eligible.

The most important thing to remember is that whatever you admit on these forms will be on record for review by any agency for the rest of your life. DO NOT try to give extract or estimated numbers of usage on your SF-86 unless they are exceedingly low numbers. You can be honest with your background investigator during the followup but there's no reason to commit those things to writing on a form that's likely to be easily accessible later on.

[1] https://www.fbijobs.gov/working-at-fbi/eligibility

zacharycohn2• 7 years ago

Was this a high school internship? If so, I think we went to the same school system.

Causality1• 7 years ago

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.

mipmap04• 7 years ago

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

lastofus• 7 years ago

Considering lie detectors are inadmissible in court, probably not. Being the cause of further investigation on the other hand...

throwawy1235• 7 years ago

Yes, you can be prosecuted for things you admit during a polygraph interview.

You can also be prosecuted for lying, since the polygraph examiners are federal investigators.

dheera2• 7 years ago

questions about foreign contacts

This sounds unreasonably intrusive IMO. What if you have a couple thousand acquaintances and friends around the world?

scarejunba• 7 years ago

It's the NSA, dude. They specifically want someone who'll be _their spook_. What makes you think they want Mr. Cosmopolitan who lunches with Erdogan's third cousin and breakfasts with the Pope? Nothing about it sounds unreasonably intrusive. The national security guys should be rightfully paranoid.

aksss5• 7 years ago

it's all about context. You're not asking for a job at the local donut shop, you're specifically getting involved in an organization that preoccupies itself with threats to the nation-state, internal and external. Kinda makes sense that they'd be intrusive. I'm not sure what the line of unreasonableness is in that context. You have no inherent "right" to work for the National Security Agency.

Spooky23• 7 years ago

Look at current events and how relationships are assets and liabilities.

Having thousands of friends and acquaintances around the world may well be disqualifying for certain positions, and assets for others.

pdonis2• 7 years ago

What if you have a couple thousand acquaintances and friends around the world?

Then that's what you say in response to the question.

bradknowles6• 7 years ago

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.

geomark• 7 years ago

Very similar to my experience, but different 3-letter agency. Two rounds. Lots of questions about drug use. I wasn't shy about it because I had had legal run-ins over it when I was young so I knew it was already out there. But examiner claimed that I was being evasive. My employer really wanted me cleared so I was coached a bit, told that unless I admit to being a spy it almost doesn't matter what I admit I have done, as long as I am truthful. I was invited back for a second polygraph. Lots more questions about drugs, some really bizarre things I had never heard of. I thought WTF, and just "admitted" to most everything the examiner asked me. He still said I was being evasive. I thought, this is stupid, it doesn't work at all, he's just guessing.

jldugger3• 7 years ago

At this point, I assume the point of the process isn't to ferret out liars, but to ferret out people who were trained to pass a polygraph under stress, on the theory that such people are more likely to be spies. It's the only thing that makes sense given the scientific unreliability, the random unfounded accusations by interviewers and whatnot.

But maybe I'm being to generous.

hiram112• 7 years ago

Did you pass?

inflatableDodo• 7 years ago

If you're particularly desirable to the managers who're looking to hire you, they'll keep inviting you to take more polygraphs, and you'll eventually pass.

Now, I am no expert on these things, but something tells me that they are doing this wrong.

"All of your previous polygraph tests indicated to us that you couldn't be trusted as far as we could throw you, however your latest one clearly shows that you have suddenly become as honest as the day is long. Welcome to the team."

fulldecent23• 7 years ago

Polygraphs can be "inconclusive" many times. Especially if you the kind of person that is uncomfortable sitting still and breathing in the same rhythm for an extended period.

myrandomcomment2• 7 years ago

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.

stephen_g• 7 years ago

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!

fulldecent23• 7 years ago

Me too. I'm interested to know when this was because I am reading between the lines and believe little has changed on the questions between when you did it and I.

At my time I was told that all interviews at a certain exit off I-95 in Maryland were done by FBI.

I expect several people reading your note might also have gone through this process and failed. Interested to hear if anyone has successfully retrieved transcripts using a FOIA request.

nocsi2• 7 years ago

Polygraphs aren’t really used for lie detection. Think of it as a tool for an enhanced interview. It allows for the interviewer to have many more dimensions of straws to grasp at in assessing you. “Lies” are assessed as anomalous readings measured against control questions. This is something polygraphers are open about and inform you of the control stage during the start. Afterwards, it’s all really an internal battle. There’s even various stages cues wherein they might leave you in the room alone to fester in your thoughts. So really it’s not whether youre a liar or not, but more of having a consistent nature

rubicon33• 7 years ago

Knowing this, it seems like it would be very easy to throw them off your lying scent.

I've had a few experiences in my past that, when brought to memory, cause fairly large adrenaline spikes. Certainly, the memories increase my heart rate by just thinking intently about them.

In theory... couldn't you bring these thoughts to memory - at random? When asked about what you had for breakfast, for example. It would appear as an anomaly... But if you did that often enough, the interviewer couldn't trust the anomalies.

nocsi2• 7 years ago

Sure if what you lied about is a big deal. The polygraph room is purposefully sound-dampened. I remember being able to abnormally hear more of my body (heartbeat, saliva, etc) in the room. What I'm getting at is that during a polygraph, it's very doubtful you're going to be daydreaming while undergoing a 4-5hr long interview lol. If you want to know how to 'cheat' the polygraph - I'll tell you.

There's no magic to it, you just have to really not give a shit about anything really. In the context of the US government, they want workers that are first and foremost, resilient to manipulation. Historically, the biggest traitors in the country have been money-driven, hence the emphasis on identifying huge debt areas. Such debt can be leveraged against people easily. The other thing to consider is, do you think they want someone that's too honest? What about in the scenario that you're being interrogated by a foreign agency, you're telling the truth but you're sweating balls. A polygrapher can latch onto these signs and use them against you. And someone that's emotionless and doesn't really give a shit about anything good or bad? Pass the polygraph with flying colors, have fun swaying someone that can't be bought off nor exempts guilt.

Smithalicious• 7 years ago

It's the classic "I already know the truth and lying will only make your punishment worse" trick that most moms seem to pull at least sometimes

tantalor• 7 years ago

Oh I get it, the title is a pun: the truth-telling machine itself is a lie.

jpmattia2• 7 years ago

I have no idea why there is not an accurate calibration of polygraphs published. Here's a straightforward calibration:

Have the subject write down a random number from 1 to 1024. Perhaps this random number is assigned via a phone app. Have the subject put the paper in his pocket.

An maximally accurate polygraph will require no more than 10 questions to determine the number in the subject's pocket.

[However, I think we all know what the result would be, which is why nobody publishes a simple calibration like the above: It is not in an trained examiner's interest to expose the inaccuracy of polygraphs.]

nxpnsv• 7 years ago

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.

jpmattia2• 7 years ago

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 superior.

throwaway2048• 7 years ago

What about if you keep it secret you get $1000

jefftk• 7 years ago

Committing to answer "yes" to every question without registering it enough to even understand it would make your polygraph "fail" even if it actually worked well in real usage.

all_blue_chucks• 7 years ago

The goal isn't to detect lies; it's to detect which lines of questioning make you nervous.

crimsonalucard• 7 years ago

Many people can believe their own lies which I guess will likely complicate any physiological pattern they try to correlate with a lie.

JackFr3• 7 years ago

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.

throwawy1235• 7 years ago

What sort of disqualifying info, if you don't mind my asking?

There were a lot of interesting questions in the psych interview, from porn use to romantic relationships and digital pirating...

And, just spitballing, I wonder if it's a crime to lie in the psych interview. I know it is during the polygraph, since the examiners are federal investigators.

JackFr3• 7 years ago

Let's just say at the time I was a bit of a heavy drinker.

And the technique basically was to spend about 15 minutes having possibly the most uncomfortable conversation I've ever had about sexual relationships, pornography, sexual fantasies, etc. -- none of which they actually cared about. The intent was to make me as absolutely uncomfortable as possible. Then he moved on to a few quick questions about drug and alcohol use, which was such a relief, that before I realized what I was doing, I had answered fully and truthfully.

blackflame70003• 7 years ago

What's interesting though is that a failed polygraph reading isn't sufficient to charge someone with lying to investigators because they would have to prove a polygraph is correct beyond a reasonable doubt. Furthermore, they wouldn't ask you a question they already know the answer to. For example, if they ask you, have you ever done drugs in the past, you wouldn't be there if they already knew the answer was yes.

wycy• 7 years ago

Can you elaborate on the way you were manipulated?

aksss5• 7 years ago

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

JackFr3• 7 years ago

Every Spy a Prince

Spearchucker• 7 years ago

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.

tempestn• 7 years ago

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

thfuran2• 7 years ago

How is that even supposed to work?

giles_corey4• 7 years ago

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...

SignalsFromBob• 7 years ago

Most interesting for me was being told I'd failed a test I was later told I'd passed. It's sheer madness.

It's pseudoscience. They might as well have [measured the size of your head][1] to make their decision.

[1] https://en.wikipedia.org/wiki/Phrenology

hestipod2• 7 years ago

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 arrive at the conclusions the entity administering the test wants to arrive at.

bradknowles6• 7 years ago

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.

jobigoud• 7 years ago

Q: Are you capable of defeating this test?

A: No.

The answer does not convey any information whatsoever.

oufoufouf• 7 years ago

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 my interviewer was much nice and seemed to give me multiple tries, telling me that they might do another one later if I really failed.

Overall the interview process was OK. I guess the only invasive part was when they interviewed my neighbors in person without telling me. (When the FBI comes knocking on your door, you freak out)

I also turned down the internship because the pay was abysmal for IT. $15 an hour.

pmarreck• 7 years ago

watching pornography as something immoral

Well, there goes everyone.

robbyking• 7 years ago

"I disagree with the premise of the question."

lovemenot• 7 years ago

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.

bradknowles6• 7 years ago

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.

xorcist2• 7 years ago

How is this not a joke?

I get the comments that it's an "enhanced interrogation technique", but it sounds like it requires the subjects to be at least a bit intimidated by it. If someone pointed a dowsing stick at you, you wouldn't be the slightest bit intimidated by it, no matter how mean looking it was.

What kind of strange culture lets a prop straight out of a 50s sci-fi flick instill respect in people? And how they do it? Surely it can't just be the Hollywood movies?

Sorry for breaking out in a bit of a rant, but I seriously can't wrap my mind around how these things could possibly be useful.

blackflame70003• 7 years ago

It's not the machine itself that's intimidating, it's the consequence of being caught lying and the accompanying loss of freedom or job opportunity.

xorcist2• 7 years ago

Sure, but nobody chose a wizard's hat or a dowsing rod, so there must be some cultural significance to it completely beyond my understanding?

aksss5• 7 years ago

If you've ever been personally interrogated by someone that knows what they're doing (police detective, etc), it's a pretty intimidating experience by itself - and completely fascinating because you realize it's completely a learned skill to do that! You may call me naive, but it really preys on your desire to tell the truth. I can understand how a "devoted" criminal can easily game the interpersonal exchange, but the average law-abiding person gets confronted with a lot of strange and conflicting emotions - desire to pursue the truth, desire to please, etc. A skilled interrogator is pretty amazing.

Now add biometrics. It's not like the polygraph is separable from the interrogator. It's a question of establishing a baseline and watching for deviations that gain significance based on experience and knowledge. The polygraph enhances the ability of the interrogator in terms of their access to biometric data of the subject, and ancillary to that is the intimidation factor that the subject feels knowing the interrogator may be more aware of your biometrics than the subject themselves.

aiyodev• 7 years ago

The reason why we settled on the polygraph and not something else is because of William Marston. He invented the early polygraph after noticing his wife’s blood pressure rose when she was angry. He also created Wonder Woman who carries a whip that makes people tell the truth. In the 1930’s he wrote a book advocating for the use of the polygraph by law enforcement. Gillette hired him for an advertising campaign to “prove” they had better razors. The public started to believe in it’s effectiveness which allowed it to start coercing confessions.

We might as well be determining guilt and innocence with a block of Kryptonite or by flipping a batarang. It’s ridiculous that it is still allowed.

everdrive2• 7 years ago

Well, if losing the dousing stick test ends your career and sends you through months of more investigation, which may or may not include interrogation, you might take the dousing stick test more seriously.

tomohawk• 7 years ago

They could probably double the accuracy by also adding in phrenology.

https://en.wikipedia.org/wiki/Phrenology

Aldrich Ames didn't appear to have any trouble passing his, but I can't help but think if they added some phrenology in, they maybe could have caught him.

https://www.nytimes.com/1995/02/19/opinion/lie-detectors-lie...

dang• 7 years ago

Some relevant previous threads:

2018 https://news.ycombinator.com/item?id=18431683

2018 https://news.ycombinator.com/item?id=18120270

2015 https://news.ycombinator.com/item?id=10002889

2015 https://news.ycombinator.com/item?id=9481385

2013 https://news.ycombinator.com/item?id=6308878

2013 https://news.ycombinator.com/item?id=6307479

2009 https://news.ycombinator.com/item?id=428489

humantiy• 7 years ago

I've always looked at the polygraph as not really a lie detector but more so as the person taking it believe their own statements or doesn't get nervous.

naiaokami• 7 years ago

I was polygraphed back in 2015. They polygraphed me three times, and then said that I failed the question regarding unauthorized foreign contacts. It was a very bizarre experience. They would often repeat stuff like "Don't try to make anything happen or stop anything from happening. Got it!?" during the questioning. I remember having to sit perfectly still, with a pad under my bottom as well as under my feet.

Amusingly, before polygraphing me I was asked if I had "read anything online" about the process, to which I shrugged and said "Hasn't everybody?" The entire process is ridiculous.

TrinaryWorksToo• 7 years ago

If we want to detect recognition of something they deny, we can go directly to the brain: https://www.psychologicalscience.org/observer/detecting-dece...

Michael from VSauce already tried to countermeasure this method and failed.

https://psychology.iresearchnet.com/forensic-psychology/poli...

https://www.sciencedirect.com/science/article/pii/S001002770...

kristofferR• 7 years ago

What drugs can you take to be able to cheat your way though a polygraph? Since polygraphs are based on producing anxiety I guess anxiolytics would work.

Would something like Phenibut suffice I wonder?

fulldecent23• 7 years ago

Also just want to say this plainly. If you ever will take a polygraph in the future, you should read about it online even if you "have nothing to hide."

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