The polygraph has long been plagued by questions
By Ishani Ganguli
ARTICLE EXTRAS
The polygraph-developed in the 1920s by John Larson, a Berkeley, Calif., policeman with a PhD in physiology-relies on the notion that people get nervous when they lie. A subject is strapped to a chair by wires and cuffs on his arm, chest, and fingers, and the "lie detector" marks his vital signs in squiggles on paper or a computer screen. If he shows signs of an accelerated heart rate, increased sweating, or faster breathing in response to an incriminating question, he's failed the test.
First conceived as a means of replacing police brutality with hard science, the polygraph quickly took on "a bluff and bluster kind of role" in police precincts, says Ken Alder, a historian at Northwestern University. "It has the same logic as torture...to intimidate people into confessing." Academic psychologists had doubts from beginning, and ...
