According to a comprehensive 2002 review by a federal panel of distinguished scientists. The study found that if polygraphs were administered to a group of 10,000 people that included 10 spies, nearly 1,600 innocent people would fail the test -- and two of the spies would pass.
"Its accuracy in distinguishing actual or potential security violators from innocent test takers is insufficient to justify reliance on its use in employee security screening in federal agencies," the panel concluded.
The polygraph examination is administered without advising the applicant they may end the exam at any time, without advising of the right to counsel, and, as evidenced by countless stories on the internet, is prone to deceptive, coerced, illegal conduct by federal agencies conducting these exams.