Add Yahoo as a preferred source to see more of our stories on Google. American inventor John Larson, right, demonstrates the operation of a polygraph at Northwestern University in Evanston, Illinois, ...

In the first decades of the 20th century, when life was being transformed by scientific innovations, researchers made a thrilling new claim: they could tell whether someone was lying by using a ...

A version of this story appeared in CNN’s What Matters newsletter. To get it in your inbox, sign up for free here. When President Ronald Reagan’s White House threatened thousands of government ...

The polygraph is not a lie detector but rather an instrument that measures a person’s physiological changes to questions posed by the examiner. An elevated physiological response to a particular ...

Malfunctions in polygraph equipment operated by the Pasco County Sheriff's Office date to July 1990, according to records released by sheriff's officials Thursday. The records, released at the request ...