Lie Detectors Penn & Teller: Bullshit! : Season 7 Episode 5
TV-14 (DLSV) Showtime 30m
Aired: July 23rd, 2009 @ 10:00 PM EST on Showtime
Polygraphs are used in thousands of investigations and job screenings. Can a machine really detect whether someone is lying? Penn & Teller will meet people whose lives were ruined by the faulty tests.
