In this 1986 exposé of the polygraph trade, CBS 60 Minutes set up a test in which three polygraph examiners chosen at random from the New York telephone directory were asked to administer polygraph examinations to four different employees of the CBS-owned magazine, Popular Photography, regarding the theft of a camera and lens. In fact, no theft had occurred.
Each polygrapher was told that a different employee was suspected as the likely culprit. In each case, the polygrapher found the person who had been fingered to be deceptive.
Interesting video. With a larger sample size and statistically significant analysis,
this type of experiment could demonstrate operator bias in results. It is actually
a very common situation, i.e. in initial applicant screening operations where there
is no known offense and expectation of deception on the part of the subject, yet
a false positive is taken as grounds for rejection.
At the end of this segment 60 minutes said legislators stopped the use of lie detectors in the private sector, but what about in courtrooms? I have to wonder how many innocent people lost their job, (have spent or still are spending) time in jail, and had their lives ruined because of lie detectors.