If you're going to rely on pseudo-scoentific bullshit, you might as well bring in some palm readers and voodoo priests instead. At least that'll be entertaining.
EDIT - Just want to add this - Never, under any circumstances, should you take a polygraph test. If you are a suspect (legally or otherwise), they will not use the results to exonerate you. If they suspect you did it, but the polygraph doesn't detect any deception, they will throw out the results as "unreadable" and pursue other means of investigating you. But if the results detect deception, they will treat it like the fucking Oracle at Delphi.
There is no machine or drug or anything else that can "detect" a lie or signs of deception. Polygraph results are purely interpretive, and anything that's given to interpretation is given to the bias of the interpreter. Polygraph results are also wildly inconsistent. That's why they are generally not admissible in court.