Isn't it true that lie detectors work on bodily anxiety reactions?

[Deja Q]

If so, if people who have anxiety or similar disorders get hooked up to such a machine, how do we know that the results will be rightly accurate?

[KitchenWitch]

1. That is a good question.

Wow, something to think about.

[KitchenWitch]

2. Delete

Damn wi-fi network.

[DelawareValleyDem]

3. They're not completely accurate

The results from them are usually not admissible in court.

[Deja Q]

6. Hmmm. So 'Doctor' Phil is hamming up the importance of his

top rated guy and his lie detector box...

Well, 'Dr.' Phil is an entertainer for one thing... and wouldn't sodium pentahol or similar drug yield more accurate results?

(that's what made me ask the question; an episode of Dr. Phil. :eyes: )

[Cannikin]

4. I've beat one once...

The trick is to have the same response to every question. Biting your tongue and clenching your toes can give it a false reading.

[Worst Username Ever]

10. Me too. A thumb tack in the shoe did it.

It was for fun, not a job. A good reader can spot people fidgeting with their mouoth/feet though, and will mark your results as inconclusinve.

[aden_nak]

5. We don't. That's why they are inadmissable in court.

And it's also why many people who fail a lie detector test the first time pass it the second time. It's because they have had a chance to calm down and relax. Well, relatively speaking. It's also how some people are able to "fake out" a lie detector test. It's about physical and mental control and relaxation. If properly prepared, there are certain types of drugs that can even help with cheating on a lie detector test, though they may have adverse affects (many substances that relax you also cause your awareness to dampen or lower your inhibitions).

[DBoon]

7. They won't be

I've heard overly anxious people tend to have a hard time getting security clearances for this reason - if you can't get reliable polygraph tests, you can never really tell when someone is really lying.

[ContraBass Black]

8. During the interpretation,

The reactions during the questions are compared to readings taken while the subject was answering questions that were already confirmed true or false.

[FormerDittoHead]

9. The REAL reason lie detectors are used...

My father was a prosecutor for 5 years here, and was one of the first in the region to use a lie detector (it actually made the news).

He told me they are wholly inaccurate. I mean, ask 5 witnesses of a crime what happened and there are going to be 5 different accounts of the facts, and all of them swearing they're telling the truth with no motive to lie.

He told me that the last thing the police / prosecutor wants to do is to go to trial. Why go through all of that bother compared to just getting a guilty plea?

My father said that as a polygraph is PERCEIVED as "scientific", it serves to intimidate a suspect into eventually telling the truth.

The suspect will be told that it will be "held against him" or "look guilty" if he refuses in some way, and they imply that positive results will exonerate him (which it will NOT). They eventually break him down and get what they want.

In the meantime the polygraph industry has done nothing to stop the spread of this myth of accuracy, and it's often used in business enviornments, along with (are you ready?) handwriting analysis, which some businesses still use to screen out job applicants.