The truth about lie detectors is that we all really want them to work. It would be much easier if, when police were faced with two contradictory versions of a single event, there was a machine that ...

The polygraph or lie detector test has been in use for over 100 years. It has been heralded as a technological marvel that allows investigators to accurately determine when someone is lying and when ...

Polygraph exams are commonly called "lie-detector tests" but experts say that's not true. The FBI and other agencies are using polygraphs to find leakers. But do they work? Federal agencies have ...

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 ...

Lie detector tests are often treated as truth machines, but they’re far from perfect. In this video, we explain how polygraphs work and why people sometimes pass them even when they shouldn’t. Rather ...

Federal agencies have stepped up their efforts over the past few weeks to find potential leakers, and some — like the FBI, the Department of Homeland Security and the Department of Defense — are ...