Lie Detectors

[londondave]

If these so called "lie detectors" are 99.9% accurate as portraid on progammes like Trisha, then Why dont we  abolish courts and jury service and just use them instead when catching criminals

[iwantthatone]

I've thought that before now too, thought not actually abolishing courts, but considering using them alongside normal procedures...

[Quizmonster]

The polygraph - lie-detector - is not universally regarded as reliable. Even its supporters claim only 85% reliability - not 99.9% - whilst the American Psychological Association puts it at no more than 61%. Click here for a web-page with lots of further ideas and links on the topic.

[Gevs1966]

You can also train yourself to beat them

[stevie21]

They detect things that accompany lies such as stress, heartrate increases etc. so they're not really *lie* detectors. As mentioned, they're not acurate enough to be used in court and with a bit of practice you can beat them.
Apparently if you lie about something so much that you start to believe it yourself then you're more likely to "pass" one of these.