First off, a polygraph test is not a lie detector test. No machine can tell if you’re lying or telling the truth. Period. This is junk science, it’s validity has long been debunked, it is notoriously unreliable and results are NOT ever admissible in court. Police use it to trick people into confessing. Here is a polygraph expert who is being indicted for teaching people (for profit) how to “pass” a test. Proof enough.
Polygraph.com owner indicted for training customers to beat the polygraph | Ars Technica.