News -- Report by National Research Council says lie-detectors tests don't work very well: http://www.nytimes.com/2002/10/08/science/08CND-LIE.html

Comment -- The problem is that the scientific evidence on the accuracy of polygraph testing is very weak. And, the test create a lot of false-positives -- that is, innocent people who are nervous or anxious can fail the tests and come across as liars. On the other hand, an calm, cool and collected liar can pass the test.

I guess the lesson is don't be impressed when a criminal suspect passes a lie detector test, or alarmed when it's reported that someone failed a test -- that person could still be innocent.

12:45:25 PM