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AIBU?

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Original poster

in thinking lie detectors might be fallible?

27 replies

mcoy · 01/03/2016 12:13

Sick and watched Jeremy Kyle... I really hope they use actors.

AIBU in thinking it's entirely possible some of these people are actual telling the truth when the lie detector says they're lying? (If they're real people in the first place)

Yes I know I'm U to watch it in the first place

OP posts:
PhilPhilConnors · 01/03/2016 12:15

Results of lie detectors aren't allowed to be used in criminal cases because they're not accurate enough.
(I'm sure I've read that anyway, might be making it up!)

ImperialBlether · 01/03/2016 12:17

If you were a psychopath it's likely your voice wouldn't change when you answered a lie detector test, so you'd get a false reading that someone was innocent.

TheEmmaDilemma · 01/03/2016 12:18

Cannot be used in criminal cases in court. But are generally believed to be reliable.

Arfarfanarf · 01/03/2016 12:18

This reply has been deleted

Message withdrawn at poster's request.

LurkingHusband · 01/03/2016 12:20

Lie detectors are as reliable as ghost detectors.

Honest.

Sallyingforth · 01/03/2016 12:26

Having been involved with a few TV shows I can tell you that absolutelynothing is true.

infife · 01/03/2016 12:29

MIGHT be? They bloody well ARE fallible!

They test reactions to a claim and are easily manipulated.

I am a confirmed atheist. If you attached a lie detector to me and asked whether god exists, and I reply that she doesn't, the lie detector will show signs that I am not lying.

If you ask a committed Christian if god exists, they will reply that she does, and the lie detector will also show signs that they are not lying.

A sociopath would presumably be able to give whatever results to a lie detector they wanted.

purpleisthebest · 01/03/2016 12:33

I'm pretty sure that at the end of the show, there's a disclaimer shown on screen (for about 3 milliseconds!) that lie detector tests are only 97% accurate or such like. That means that at least 3 of 100 people who say they were telling the truth, are right.

OurBlanche · 01/03/2016 12:34

I can answer that one... sort of.

A few years ago I took part in a psychology experiment. They were looking at lie detectors and how people react to them.

I volunteered as I had always wanted to test myself against the machine - my degree involved some psych and I have always wanted to test the 'mind over matter' theory.

So they hooked me up and I played with the machine. They gave me a list, lie, lie, truth, lie, truth, truth and I had to respond accordingly. Simple non visible relaxation techniques can fool the machine into thinking the truth is a lie and a lie is the truth.

The issue, which they would not let me play with (and I actually begged for more time to try), was that the machine did measure responses while I was reading the list. Whilst my responses where the same whilst I listened to and answered the question there was a measurable fluctuation when I read the list. I think that, with a bot of practice I could cheat that too. Especially as the fluctuation got weaker as the test went on, even without my knowing it was being measured.

OurBlanche · 01/03/2016 12:36

infife - your example is a bit weird. Lie detectors measure whether the person being tested is lying or not. They don't measure delusions or mistaken beliefs. So both you and the committed Christian would be telling the truth, as you knew it!

Which is why psychopaths are not given the test... they don't have the same relationship with true/false.

Original poster
mcoy · 02/03/2016 09:48

Blimey this show is brutal

I'm glad to hear it's not true sallyingforth

Is it exploitation of vulnerable people though or paid actors?

OP posts:
ItsAllGoingToBeFine · 02/03/2016 09:51

It is exploitation of vulnerable!e people Sad Angry

TaraCarter · 02/03/2016 09:54

They are very fallible. It just measures heart-rate. How easy would it be to be experiencing stress despite telling the truth? Answer is:

in thinking lie detectors might be fallible?
OurBlanche · 02/03/2016 09:57

It just measures heart-rate. They can measure many things: blood pressure, respiration rate, galvanic skin response, eye movements, muscle tension, swallow reflex.

They all use the 3 autonomic arousal indicators: heart rate/blood pressure, respiration, and skin conductivity

Sallyingforth · 02/03/2016 09:58

Exploitation of vulnerable people who are individually worked up beforehand to believe they are correct, so as to maximise the conflict in front of the cameras.

ChazsBrilliantAttitude · 02/03/2016 09:59

I watched a US programme where ex cons were explaining how they would fake lie detector tests. IIRC they would put something sharp in their shoe and press down on it when they told the truth (e.g. confirmed their name) but not when they lied. That way they got spiky responses for both the truth and lies so they couldn't be clearly differentiated.

pippistrelle · 02/03/2016 10:00

Yes, the Jeremy Kyle lie detector practitioner claims 95-97% accuracy: others, of course, say it's all bollocks. But even if you accept the Jeremy Kyle claim, given the number of tests they carry out, that's still a lot of people denounced as liars - with all the fallout - when, in fact, they're telling the truth. Why anyone would expose themselves to it is a mystery.

Original poster
mcoy · 02/03/2016 10:01

Ugh how sick. Think I shall have to vote with the remote.

How do the producers/presenters etc live with themselves?

OP posts:
CreamofTartar · 02/03/2016 10:02

Of course they're fallible, OP. They're not Veritaserum. They measure certain stress responses which can indicate a (conscious) lie, but anyone can learn to circumvent them easily with practice. And as another poster said, they don't detect mistakes, false beliefs, delusions. If I murdered twenty people in a fugue state but genuinely believe I was in bed with a cup of cocoa at the time, the lie detector won't register anything.

TaraCarter · 02/03/2016 10:04

You're right, I over-simplified. Blush

RockUnit · 02/03/2016 10:05

If they're basically measuring stress/anxiety then someone who is honest but stressed about possibility of being found a "liar" when they weren't, would fail, wouldn't they? And the swaggering liar who couldn't care less might not fail the lie detector test.

TheWeeBabySeamus1 · 02/03/2016 10:09

Complete exploitation. Someone who had a friend who worked for the production team told me that they give the guests an allowance for "expenses"... its not much (less than £100) but if you're skint it must be tempting.

And I don't believe the lie detector, as PPs said its not accurate and can easily be manipulated if you know how to.

Plus JKs a massive bell end Grin nowt to do with the lie detectors but always worth a mention.

Original poster
mcoy · 02/03/2016 10:10

It seems really sad that perhaps the less educated (although you probably have to be either utterly desperate or a bit dim to apply to the show in the first place?!) will probably take the lie detector as gospel

OP posts:
Oldraver · 02/03/2016 10:10

I know it makes for good bad show but I have never understood why they are so adament over the 'your lying' thing. Surely by now with the amount they do there would be people falsely accused of lying.

That is even before you get to the people that actually believe their own lies..I would of thought they would show up as telling the truth when actually are lying

But it all makes for good shouty tv

Original poster
mcoy · 02/03/2016 10:18

Plus JKs a massive bell end

Grin completely. It's actually turned my stomach how he's acting like the moral high ground while fronting such a corrupt exploitive show

OP posts: