Truth and Lies…

Here we focus on the effectiveness and legalities of using the lie detector to prevent dishonesty and/or identify culprits of dishonest acts.

Do you know who you employ?

It is a known fact that the majority of crimes are committed by employees. Some of these crimes could have been avoided if pre-employment polygraphs had been carried out and these crimes can be stopped by identifying the culprits.

What are the “do’s and don’ts” involved in using this valuable tool?

Q. Can I force an employee to take a polygraph test? A. No. You need their permission at the time or it should be written into an employment contract that both the employer and employee have previously signed. Every polygraph examination should be preceded by the completion of a “polygraph consent form”. Bear in mind the suspicion created when an employee refuses to consent to a polygraph examination without reasonable grounds. Q. Can I dismiss an employee for failing a polygraph test?   A. No. The information can only form the basis of an investigation and must be supported with further evidence which proves within a “balance of probability” that an offence has taken place. The polygraph can therefore only be used as supporting evidence in a disciplinary hearing and it is not accepted as evidence in a criminal trial, where guilt has to be proven “beyond reasonable doubt”. Q. Can an employee be questioned about more than one issue in the course of one test? A. Yes. The success of a polygraph examination is based on the composition of the questions, therefore the series of questions to be asked must be carefully formulated and not vague or generalised.   Q. How many relevant questions can be asked in the course of the test?   A. Preferably, not more than 4. Q. Can a pregnant female be polygraphed?   A. No (as a rule). Although there is no medical evidence to date that the polygraph can cause any harm to the mother or unborn child.   Q. How accurate is the polygraph test?   A. The American Polygraph Association has a compendium of research studies available on the validity and reliability of polygraph testing. The 80 research projects listed, published since 1980, involved 6 360 polygraph examinations or sets of charts from examinations. Researchers conducted 12 studies on the validity of field examinations, following 2 174 field examinations, providing an average accuracy of 98%. Q. If a person is a habitual liar, can he still be polygraphed? A. Yes. Q. Is it legal to subject prospective employees to a pre employment polygraph test?   A. Yes. But only if they agree to it. As a matter of routine, polygraph testing should be considered for inclusion in employment contracts. Q. What elements could have a negative effect on a polygraph?   A. Noise, language and distraction.   Q. Does sleep depravation affect a polygraph? A. No. This is situational and the examiner must still make the decision on whether the examinee should be tested. The USA Department of Defense Polygraph Institute (DODPI) conducted research to assess if variables such as number of hours the subject slept prior to the test, the subject alertness during the test, the subject’s general health, the subject’s level of physical discomfort’ the subject’s use of alcohol, nicotine and coffee prior to the test, had any impact. In general the situational variables had little impact on test outcome (US Joint Security Commission Report 1994)   Q. Do the electrolytes in your body effect the polygraph?   A. No.   Q.  What about prescription drugs for post traumatic stress disorder that calms the brain or a drug that has “ephedrine” in it?   A. No.   Q. Anabolic steroids?   A. No.   Q. Is it true that if you undergo a test on an empty stomach it would affect the result?   A. No.   Q. Does liquor affect the result of a test?   A. The US Department of Defense Polygraph Institute (DODPI) conducted research to assess if variables such as: number of hours the subject slept prior to the test, subject alertness during the test, the subject’s general health, the subject’s level of physical discomfort or if the subject’s use of alcohol, nicotine and coffee prior to the test, had an impact. In general the situational variables had little impact on test outcome (US Joint Security Commission Report 1994). However, the examiner will still assess the situation and, in most cases, will not perform the test due to the argument of consent whilst under the influence.   Q. I’m told that if I’m nervous, I could fail the test. Is this true? A. No. This is a long standing belief that holds no truth whatsoever. Everyone who takes a polygraph examination will be nervous, whether they intend lying in the exam or not. The polygraph exam identifies truth and deception, no matter the level of nervousness in the subject.   Q. How does the polygraph detect lies?   A. When people lie about something important, changes occur in our bodies that we have no control over. The polygraph records those changes. One of the two nervous systems in our body is called the Autonomic System. We have no conscious control over this system. The Autonomic System in turn, consists of two systems – the Sympathetic and the Parasympathetic. When we lie, it creates physiological changes at the Sympathetic level beyond our control and the polygraph records these Sympathetic arousal responses.   Q. Will it work on someone with no conscience – a psychopath, for example?   A. Yes. Research has shown that the polygraph is just as accurate on psychopaths (in fact even more so in many cases) as it is on non-psychopaths. This research has been in the form of practical field results, not theoretical academic work.   Q.  Surely you’re biased towards whoever is paying for the exam? (If it’s a company, for example, I find it hard to believe that you won’t give them the result they’re looking for?)   A. When we conduct examinations, we are partial to neither party and prejudiced to nothing. If one party, however, is looking for something different to the truth to be reported by us, then they have come to the wrong place. Our polygraphists are registered with both the American Polygraph Association and the Polygraph Association of South Africa and are therefore bound by codes of ethics as well as standards and principals of practice. Lastly, from a commercial perspective, unethical practice is a sure way to ruin one’s reputation and consequently, ones business. Symbiotix will not entertain bias under any circumstances. The truth is out there! Thank you for taking the time to read our blog. Keep on checking back with us for more useful and relevant advice. If you would like to contribute, comment or receive more professional advice please Contact Justicia Investigations.