A method of detecting lie detection including the steps of first conditioning the subject to produce an involuntary physiological response triggered when the subject provides false statements; and secondly asking the subject to state whether each of series of statements presented to the subject are true. As the subject answers, the subject is monitored for the conditioned involuntary response. Detecting whether the subject is providing false statements is based on whether the involuntary response is observed during these answers. A system ( 19 ) for lie detection includes a computing device ( 21 ), a controller ( 40 ), and at least one conditioning interface ( 42, 44 ).