Here’s an interesting report on how the Department of Energy (responsible for the nations nuclear weapons arsenal) uses the polygraph (lie-detector) for counter-intelligence operations. The report observes that a polygraph test can’t reliably tell if someone is answering the questions truthfully (there are too many ways to fool the machine, and the physiological reactions it’s looking for aren’t proven to indicate truthfulness). However, I found it interesting to note that the polygraph is still useful as a deterrent, even though its results cannot be relied upon.

Click here to read the report (80K - PDF)