Who is the most prominent polygraph examiner of all times?
Leonarde Keeler (1903-1949), born in North Berkeley, California, USA, is the most prominent polygraph examiner of all times. Having conducted over 30,000 polygraph examinations, Leonarde Keeler is one of the world’s foremost scientific criminologists, whose contribution to the stature of the field of lie detection is merely immeasurable and invaluable. In 1925, Leonarde Keeler (a Stanford University psychology major working at the Berkeley Police Department), developed two significant improvements to Larson’s polygraph: a metal bellows (tambour) to better record changes in blood pressure, pulse and respiration patterns, and a kymograph, which allowed chart paper to be pulled under the recording pens at a constant speed. In 1936, Keeler added a third physiological component to his polygraph – the Psychogalvanometer – a device for measuring changes in a person’s skin resistance. This version of Keeler’s polygraph was the prototype of the modern polygraph, and Keeler himself is therefore
