When does a judge request to a polygraph to be used in court?

Question

I need to know how I can find out in what instances a polygraph would be used in the court room.

Answer 1

Never.
Polygraph results are not admissible in court. That's because it's been proven over and over again that a polygraph is not an accurate method of detecting lying, and they can easily be "tricked" by a savvy person. They also produce a fairly large number of false positives. Since no legally valid conclusion can be drawn from the results, the results are not admissible in a court of law.

Prosecutors and police will often ask a suspect to voluntarily take a polygraph test despite it's inadmissibility -- they do this for several reasons.
First, someone who's actually guilty will often refuse to take one (since many people believe they're accurate even though they're not), and so police use a refusal as an indication that they should continue to investiate someone. Second, if the suspect takes the test and passes, they will often still tell the person they failed, in an attempt to elicit a confession (the supreme court has upheld the police's right to lie to suspects in an attempt to elicit a confession, and they do it all the time). And third, in the absence of any other evidence, a person who passes a test will sometimes be excluded from the "hot list" of suspects for a crime and the police will focus their efforts elsewhere, although they know the tests aren't reliable.

Polygraphs are used most often as an intimidation factor, more than anything else.

Answer 2

A party can always try to have a polygraph results admitted as favorable evidence by attaching to a Motion with expert witness affidavit, only to be objected to by the other side. Although a Polygraph is not admissable evidence. HOWEVER, the seed has been planted for the judge to consider in his head - and may affect his decision.

Answer 3

Polygraphs are inacurate and easily manipulated so they are inadmissable in US court rooms. Even the U.S. Government argued before the Supreme Court against the use of the polygraph because it is so easy to manipulate (United States v. Scheffer.) The Justices wrote, "...there is much inconsistency between the Governments extensive use of polygraphs to make vital security determinations and the argument it makes here, stressing the inaccuracy of these tests."

Answer 4

A judge cannot request a polygraph in the USA. Period. Polygraphs are too unreliable to be admitted. Same with Psychics. Interestingly, it can be addressed in court whether the defendant submitted to a polygraph, although the polygraph itself cannot be admitted.