Polygraph Testing

Polygraph Testing to Determine Guilt

Polygraph testing has become an acceptable practice to determine whether employees are lying about involvement of fraud, theft and other criminal activities at their employers. With misappropriation of resources and misconduct costing companies a lot of money it has become essential to find a way to get to the truth, especially for the purpose of evidence in disciplinary hearings.

A recent scenario unfolded at a pharmaceutical company in South Africa where the third to the fifth respondents were found guilty of company property theft after polygraph testing revealed their involvement in stock theft by the employer. However, the Labour Court found that the evidence was not admissible because the questions used in the test were too broad and could not serve to show to that the respondents were lying. The Court noted that the test results could not be used to indicate guilt, only deception.

Employers can still use polygraph testing, but cannot and should not solely rely on the results of the test as evidence of misconduct, theft, fraud or misappropriation of company resources. It is imperative to abide by the strict rules for usage of the tests to ensure that the Labour Court or the CCMA does not dismiss the test results as unreliable.

The employer must discuss and agree with the polygraph examiner on the questions that will be asked since any vagueness in the questions will mean that the results of the test will be worthless.

The employer may not force the employee to agree to polygraph testing and should not take refusal to submit to such a test as any form of admittance to guilt. This also means that the employer cannot dismiss the employee should the employee not be willing to take a polygraph test, unless it is an express term of the employment contract that the employee agrees that he shall submit to a polygraph test as and when requested. In addition, the employer needs to get written consent from the employee for the test though not compulsory, but certainly worth the effort to ensure that the results will be admissible.

The employee must provide informed consent and this means knowing that submitting to the tests is not compulsory and the employee will not be dismissed for refusal to undergo the test. The employee should furthermore be informed about the reasons for the testing and a thorough explanation provided as to the types of questions that will be asked, what the process entails and how long it will take. If the employee wishes, they may have an interpreter or representative present at the testing, subject to the condition of not interfering in the testing process.

The employer may use polygraph testing for the purpose of investigating theft or misappropriation of company resources or assets where the employer has reason to suspect involvement of the employee, and where the employee had access to such property under investigation. Further to this, the employer must also have suffered economic loss or injury because of the incident whether such entails the usage of illegal drugs or alcohol which could lead to injury or damage of company property because of the inability of the employee to perform their duties as a result of intoxication or because of deliberate action by the employee to cause damage or steal from the company.

The employer may also use the polygraph tests in cases where dishonesty is suspected such as fraud. The tests should be performed by approved and experienced examiners as they are often called in as expert witnesses on how the test was conducted.

At this stage, polygraph testing is still fairly new in workplace application and there is no legislation specifically controlling the usage of the tests and the protection of the employee’s rights in this regard. It is therefore recommended that the employer and employee, where allowed, make use of experienced and reputable labour law attorneys in overseeing the process of investigation and application of the tests to ensure fairness, correct application and protection of the rights of employees.


*NB this article is for information purposes only and does not constitute legal advice. You are advised to consult with us before using/relying on this information.

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