Why do courts not use lie detectors and evidence?

Question

I have seen that alot of courts dont use lie detectors, but why ? the results are pretty solid or go i have been told.

Answer 1

you honestly think the court is willing to spitt out money to help a case??? i have never heard of that. it probably has to be court injunction to do that one. mostly the court system takes our money. they say that people are innocent until proven guilty well i think its more like guilty untill proven innocent or in paris hiltons case innocent with the flippen CASH! but i honestly think they should do a lie detector test. why not i mean we might even without knowing it be accuseing the wrong person. so i totally agree in it i think it should be required like a U/A (drug test)

Answer 2

The results are not solid. Many people can pass a lie detector test when guilty. Many people fail a lie detector tests when innocent.

Answer 3

Polygraph tests do not meet the necessary standards to be accepted as scientifically accurate evidence. In order for scientific evidence to be admitted into court, the method used to obtain the evidence has to be widely accepted in the scientific community as being accurate. There are a variety of factors that can effect a polygraph test. A person's nerves can result in false results. In addition to this, a person who believes their lies can "pass" a polygraph test even when they are being deceitful. These things bring the validity of the test into question; therefore, the results of a polygraph are not admissable in court as evidence. The polygraph test does serve as a useful tool for police investigations though to help pinpoint suspects.

Answer 4

Lie Detectors are not accurate because the results could be affected by the emotion of a person and deceivers can manuever the test by being stable during questioning.

Answer 5

Lie detectors are not admissible because there is no proof, to a scientific degree of certainty, that they are 100 percent accurate.

It also depends on the polygrapher as well.

The results would be hearsay. And hearsay, though probative and relevant, is not admissible at trial.

Answer 6

Not such a black and white question :) Most states just don't allow them in proceedings. Wikipedia offers some guidance and a place to start, but you may have to search by each state: "In 2007, polygraph testimony was admitted by stipulation in 19 states, and was subject to the discretion of the trial judge in federal court. The use of polygraph in court testimony remains controversial, although it is used extensively in post-conviction supervision, particularly of sex offenders. In Daubert v. Merrell Dow Pharmaceuticals (1993),[43] the old Frye standard was lifted and all forensic evidence, including polygraph, had to meet the new Daubert standard in which "underlying reasoning or methodology is scientifically valid and properly can be applied to the facts at issue." While polygraph tests are commonly used in police investigations in the US, no defendant or witness can be forced to undergo the test. In United States v. Scheffer (1998),[44] the U.S. Supreme Court left it up to individual jurisdictions whether polygraph results could be admitted as evidence in court cases. Nevertheless, it is used extensively by prosecutors, defense attorneys, and law enforcement agencies. In the States of Massachusetts, Maryland, New Jersey, Delaware and Iowa it is illegal for any employer to order a polygraph either as conditions to gain employment, or if an employee has been suspected of wrongdoing. The Employee Polygraph Protection Act of 1988 (EPPA) generally prevents employers from using lie detector tests, either for pre-employment screening or during the course of employment, with certain exemptions.[45] In the United States, the State of New Mexico admits polygraph testing in front of juries under certain circumstances. In many other states, polygraph examiners are permitted to testify in front of judges in various types of hearings (Motion to Revoke Probation, Motion to Adjudicate Guilt). In 2007, in Ohio v. Sharma, an Ohio trial court overruled the objections of a prosecutor and allowed a polygraph examiner to testify regarding a specific issue criminal examination. The court took the position that the prosecutors regularly used a polygraph examiner to conduct criminal tests against defendants, but only objected to the examiner's testimony when the results contradicted what they hoped to achieve.[46] Dr. Louis Rovner[8], a polygraph expert from California, tested the defendant and testified as an expert witness both at a pretrial admissibility hearing and at trial. The defendant, who had been charged with sexual battery, was acquitted.[47]"

Answer 7

Nowadays court isn't about justice anymore... its all about money... most lawyers will say anything if you pay them enough...

Anyway lie detectors aren't always accurate

Answer 8

NO court will use polygraphs. It is not permitted. They are notorious unreliable and the results can be skewed by many things.

Answer 9

I don't know but people can fake them out if they are calm enough and don't get tensed up. Maybe that's why they can't throw someone in jail cause a machine said they are lying.

Answer 10

they are not solid, and lie detector tests are easy to cheat.

http://www.google.com/search?hl=en&q=beating+a+lie+detector