Should You Agree to Take a Polygraph (Lie Detector) Test?

Have you been asked to take 
a lie detector or polygraph   test by the police? Here's what 
you need to know before agreeing. As a general rule, say no to the polygraph 
test, and consult with an attorney. The police may suggest you take the test 
to clear up any allegations against you,   but the truth is it carries risks for you. In Michigan, polygraph test results 
aren't admissible in court. However,   they can still massively 
impact criminal investigations.

During a police polygraph, 
you're alone with an examiner,   without any legal support from an attorney. Examiners may use emotional tactics 
to elicit information or confessions,   which can be used against you later. Remember that the examiner, who is 
usually a law enforcement officer himself,   is not your friend or ally. His goal is to gather 
evidence against you, not to clear your name. So protect your rights, and seek legal 
advice before facing a polygraph test..

per YouTube