In the past, these tests were often performed on witnesses or suspects to advance police work and support criminal investigations. They have also been used by government agents and lawyers to interrogate suspected criminals. After all, polygraph tests have even been used by employers to determine whether a candidate or employee is lying. Polygraphs are not admissible in court if the State does not recognize them as valid examinations, if both parties do not require that they be admitted as evidence in the States that admit them, if the law prohibits their use in certain situations and/or if a judge refuses to admit them in a particular case. This difference is what the polygraph test is. According to the American Psychological Association, “a model of a greater physiological response to relevant questions than to control questions leads to a diagnosis of `deception.`” They proclaim, “Most psychologists agree that there is little evidence that polygraph tests can accurately detect lies.” The laws and problems associated with polygraph testing can often be difficult to understand without the help of a lawyer. Each jurisdiction also has different procedural requirements for performing polygraph tests and interpreting their results. They may also have different clauses in their regulations that do not apply in all states. An experienced defense lawyer can discuss the results of your test and explain what they might mean for your case. Your lawyer can also inform you of your rights as a defendant, discuss your possible legal options (e.g. Plea Agreement, go to court, etc.) and be represented in court if necessary. More importantly, the court left it to the states to decide whether the test could be presented to the court. Today, 23 states allow the admission of polygraph tests as evidence in a trial, and many of these states require the consent of both parties.
Third, the prosecutor should argue that the results of polygraphs are inadmissible under section 403 because they are prejudicial, misleading and time-consuming. United States v. Williams, 95 F.3d 723, 729-30 (8th Cir. 1996) (polygraph results may mislead the jury); United States v. Pettigrew, 77 F.3d 1500, 1515 (Cir. 5, 1996) (unilateral polygraph examinations are almost never permitted under Rule 403); United States v. Sherlin, 67 F.3d 1208, 1216-17 (6th Cir. 1995) (Rule 403 is an appropriate reason for the exclusion of polygraphic results even according to Daubert), cert. refused, 116 p. Ct. 795 (1996); United States v. Kwong, 69 F.3d 663, 668 (2d Cir.
1995) (the polygraph questions were ambiguous and therefore inconclusive for the central issues of the case), certificate refused, 116 p. Ct. 1343 (1996). When you perform a polygraph test, you are connected to the test via sensors on the chest and fingertips. While you may be familiar with the image of a polygraph pen wildly scraping the results on a sheet of paper while the subject answers questions, today`s tests are usually done using computerized systems. Whether a polygraph test is admissible in court depends on jurisdiction. For example, the eligibility of polygraphs varies considerably by state. However, they can generally be divided into two main categories: States that consider the test results to be totally inadmissible and those that admit them in court, but only if they are presented with the provisions of the parties. In other words, the latter category requires that both the suspect and the prosecutor agree to admit the results. More recently, in 1998, in U.S. v. Scheffer, the Supreme Court issued an opinion in which it stated that polygraphs do not need to be admitted as evidence in military trials unless a judge gives permission in accordance with the Daubert standard.
The EPPA prohibits most private employers from using these tests for candidates or current employees. Employers are also not allowed to take action against an employee (e.g., dismissal, discrimination, discipline, etc.) if the employee refuses to take a test under the law. The same goes for law enforcement. Again, you cannot be pressured to undergo a polygraph test, and your refusal cannot be used as evidence against you in court. But many court decisions have meant that this will not be the case. Although polygraph technology has continued to improve and the questioning process has become more systematic and standardized, scientists and legal experts have not agreed on the effectiveness of the device. Over the years, the U.S. Supreme Court has issued numerous decisions on whether polygraph tests should be allowed as evidence in criminal trials. Before Larson`s invention, courts treated lie detection tests with suspicion. In a 1922 case, a judge forbade the presentation of the results of a prepolygraphic lie detector to the court, fearing that the test, despite its unreliability, could have an undue influence on a jury`s opinion. Although it is not usually recommended, a person may need to take a polygraph to prove their innocence.
However, it is important to remember that these tests are not the most reliable form of evidence. In other words, someone who is innocent may still seem to be lying about these tests because of nervousness or fear. Law enforcement agencies and/or the prosecutor can then use these results against the person if they have voluntarily submitted it.