A modern (not like the one in the movies usually) lie detector which is conducted by a PROFESSIONAL (not just some Joe who took a week long course) is VERY VERY reliable.
In fact, from my experience, people who don't want to take them, are usually lieing.
Secondly, that stuff from the movie that was mentioned is bull$hit. That is hollywood crap. It is very VERY VERY hard to trick a lie detector, assuming you don't have a serious mental complication.
In fact, modern professionally administrated lie detectors are so accurate that the mossad, the shaback, and the CIA feel confident enough to use it on THEIR OWN AGENTS to verify truthfulness.
Don't believe anything in the movies.
Whether or not it should be allowed in court is a more complicated and seperate discussion, but as far as I'm concerned, if you're innocent, and really want to prove it, take one. If you're innocent you'll pass.
And for general screening, they're useful for guidance, but I wouldn't trust polygraphs in any specific instance.
http://www.fbi.gov/congress/congress01/senser071801.htm -- "As there are elsewhere in the Intelligence Community, there will be unexplainable false positives and, as we saw in the Ames case, false negatives. On balance, however, we believe the potential for damage to be done by traitors outweighs these concerns."
There was a thread a while back here on FR about detecting minute thermal changes around the eyes while lying. It's an evolutionary response, the article said, for reflexively looking for an escape route. I'll have to find out more about that; it sounds interesting. It would be great for swearing-in ceremonies for politicians.... Time for bed.
Like being a muslim?
Islamic Concept of Al-Taqiyah to infiltrate and destroy kafir countries
Anita Hill took one, Clarence Thomas declined.
Do you figure Thomas was lying because he didn't take it?