Can a Judge Order a Polygraph Test?

The polygraph test, often associated with lie detection, remains a contentious tool in legal proceedings. This article explores the legal implications of whether a judge can order a polygraph test, its reliability, and its relevance in court.

The Inadmissibility of Polygraph Tests in Court

One of the primary reasons for the inadmissibility of polygraph results in court is the lack of scientific basis for the test. Unlike other forms of evidence, a polygraph does not measure a person's truthfulness based on a scientific principle. Instead, it measures biological responses to questions, which can be influenced by various factors unrelated to truthfulness. These responses are then interpreted by a polygraph operator, an element of subjective judgment that further compromises the reliability of the test.

The Federal Rules of Evidence [1] state that polygraph results are not admissible over objection in any U.S. court. This is because the test is notoriously unreliable and fails every test of admissibility, including checks for reliability and accuracy.

Application of Polygraph Tests in Pre-Sentence and Post-Sentence Conditions

Despite its inadmissibility in court, a judge can still order a polygraph test under certain conditions. For instance, if a person is on pre-sentencing release or post-sentence probation, a judge may order a polygraph as a condition of supervision. The results of such a test can be used to determine whether an individual needs to undergo additional treatment, such as drug or alcohol rehabilitation or mental health programs. Failure to comply with these conditions can result in automatic violations.

Moreover, a failed polygraph test may justify warrantless searches of a person's property or person by law enforcement. However, it is crucial to note that these results cannot be used as evidence in a court of law.

Legal Precedents and Manipulation of Results

A case in point is the situation involving a suspect who insisted on a lie detector test, believing it would clear things up. The suspect passed the test, but law enforcement misled him and his attorney by claiming he had failed. This misinformation was only revealed during a pre-trial hearing when the defense attorneys conducted an intense cross-examination. The suspect then succumbed to prolonged questioning while under the influence of drugs, admitting to false statements.

This case highlights the potential for manipulation and the futility of relying on polygraph tests in legal proceedings. The polygraph does not provide objective evidence of truthfulness and can be easily influenced by various external factors and subjective interpretations.

Conclusion

The polygraph test remains a controversial tool in legal proceedings due to its lack of scientific rigor and the potential for manipulation. While judges may order polygraph tests under specific circumstances, the inadmissibility of these results in court underscores their limited usefulness. For these reasons, judges typically do not order polygraph tests, and legal professionals should be cautious in their reliance on such tests.

References:

[1] Federal Rules of Evidence, Rule 702