The real use of [psychophysiological measurements] is therefore probably confined to those cases in which it is to be found out whether a suspected person knows anything about a certain place or man or thing.
-- PROFESSOR HÜGO MUNSTERBERG, 19081
In 1958 I agreed to supervise two freshman medical students who had been awarded summer fellowships. Bright and full of energy, they made short shrift of the project with which I had thought to keep them busy for three months. I needed a new experiment to last us through July and August. Intrigued by the polygraphic equipment in my laboratory, my two assistants had asked if I did any lie detector work, and I had been forced to admit that I knew nothing about the subject. Equipped as we were with time, facilities, and ignorance, we resolved to do an experiment on lie detection.
Using student volunteers as our experimental subjects, we would have them enact mock crimes and then try to separate the "guilty" from the "innocent" by means of their physiological reactions during a stan-