KidZone Science
The Accuracy of Polygraph Testing

The accuracy level of the test results depend more upon the examiners interpretation of the records rather than the evidence, recorded by the machine.  It can also depend on the questions that are used to determine the base line of the subject.  A study was done to determine the accuracy of polygraph testing, and the results of the study were that approximately 37% of the interpretations done were inaccurate.  When 100 charts (50 innocent, 50 guilty) were shown to different examiners, 37% of the innocent charts were given a guilty result.  There have also been cases where the polygraph test results have been false because the subject remained tense throughout the entire tests.  This would have tampered with the baseline results, therefore tampering with the overall test results as well.