Lie detector tests are often treated as truth machines, but they’re far from perfect. In this video, we explain how ...

(CNN) — A polygraph, or lie detector test, given to porn star Stormy Daniels in 2011 shows that she gave truthful answers to the questions: "Around July 2006, did you have vaginal intercourse with ...

Polygraphs are frequently used in criminal investigations, but rarely used in court. How do polygraphs work? The idea behind the polygraph, which was first developed in the ‘20s, is that l ying causes ...