POLYGRAPH TESTING IN THE WORKPLACE
Recently I have been asked about the use of Lie Detector or Polygraph Testing in the workplace. A contentious and controversial topic, with no legislation to control the use of the test!
So how do we best use polygraph testing? There are some rules relating to the tests that need to be adhered to in order for them to be considered reliable, fair and useful in the CCMA .
An employee must consent to the test in writing and it must be informed consent
The employer should agree with the Polygraphists on the questions to be asked. They should be clear, unambiguous and not be vague.
Undergoing the test must be voluntary, the reason for and the type of questions should be explained.
The employee may have an interpreter present and/or an examiner that can communicate in the home language.
You may use a polygraph to investigate specific incidents where there has been loss or damage to the Company, property etc and there is reasonable suspicion that the employee was involved in the incident.
The results should only be made known to an authorised person, such as the person requesting the test or who authorised the test.
The polygraphist should testify at the disciplinary hearing and arbitration proceedings as an expert witness on how the test was performed, their qualifications, the type of questions and the test used.
And the results must be supported by other independent evidence.
In summary, you cannot rely on Polygraph evidence alone in the disciplinary process. The polygraph does not prove that someone is actually dishonest or lying, nor does it prove that someone is guilty. It is merely an indication of deception. The use of a polygraph result on its own is not sufficient to prove that the dismissal was fair.
The risk of conducting a Polygraph without corroborating evidence was demonstrated at a recent hearing I chaired. There was no evidence that tied the suspect to the misconduct, other than that he had failed a polygraph. With no supporting evidence the employee was found not guilty.
The potential outcome is that the relationship is potentially damaged; there is a breakdown in trust. You believe him guilty but are unable to prove it. If the employee is innocent he may feel maligned and you lose loyalty. If he is guilty there is a feeling of being invincible and having beaten the system – often very damaging to your business.