Polygraphs, popularly known as lie detectors, measures a person's physiological status when asked a pre-determined set of questions designed to evaluate truthfulness.  Polygraphs measure heart rate, respiration, blood pressure, and skin conductivity.  They remain controversial and have been so since their invention in 1921 by a University of California Berkley medical student and a police officer.  In fact, the US Supreme Court (cf. U.S. v. Scheffer, 1998), have repeatedly rejected the use of … [Read more...]