FAQ – Frequently Asked Questions

A polygraph examination is a investigative tool, conducted by a forensic psycho physiologist to determine whether a person is truthful or not to the relevant questions.

A polygraph examination, previously known as a lie detector test is administered using a multi-channeled computerized polygraph instrument that measures respiration, skin conductivity, relative blood volume and pulse changes. After a stimulus is applied (i.e. a question is asked) the physical responses are recorded and analysed.

Polygraphists have been accepted as expert witnesses by the CCMA. The Polygraph results maybe regarded as an aggravating factor, especially when there is other evidence of misconduct. It can thus be used in support of other evidence.

The Lafeyette is said to be 98% accurate. In general a result given by a qualified forensic psycho physiologist, using a recognized instrument, technique and scoring system will be between 92% to 98% accurate.

There are many websites and individuals that claim to give training and tips on how to pass the test when you guilty. Because the polygraph instrument records physiological changes that are controlled by the automatic nervous, it would require an individual to override his or her automatic brain in order to achieve this.

No! There are nominal amounts of current passing through the instrument, none of which will enter the body. The blood pressure cuff is the only attachment that is likely to cause a little discomfort due to pressure required for measurement.

It is not advisable as the test, by it’s very nature causes stress. This may be harmful to the expecting mother. We advise that the examination be conducted after birth or alternatively that a Forensic Assessment Interview be conducted instead.