Estelle Dreyer -polygraphy expert.
By Blake Wilkins
All the digging around at the Zondo Commission trying to establish a basis for truth from a tangled web of lies brings our wooden puppet friend Pinocchio to mind.
If fairy tales could be converted into reality, then many of those testifying before the venerable judge would find themselves tripping over their extremely long noses.
Perversely, it’s probably true to claim that those seeking to deflect blame while giving evidence have expanded the world’s volumes of fairy tales way beyond what Carlo Collodi, author of The Adventures of Pinocchio, could ever have imagined.
That’s why my interest was piqued during a chance meeting with diminutive polygraph expert Estelle Dreyer in Stellenbosch. Her field of expertise is in forensic psycho-physiology. She worked in military intelligence and lectured in polygraphy at the CSIR in Pretoria before opening her own polygraphy business. For many years clients in the public and private sectors used her services.
Most of us realise that the tap-dancing we’re witnessing by so many of those appearing before the incredibly patient Justice Zondo is simply a window into a national malaise that is slowly throttling South Africa’s future.
What holds us in thrall is the apparent inability of our country’s rulers to excise the rot, to slice away the spread of gangrene before we all succumb to the poison. Or are we witnessing the euphemistically named ‘long game’ that moves slower than the cm per year of an Arctic glacier?
Can you imagine the impact of introducing effective polygraph testing across every level of upper management in the private and public sectors in South Africa?
What a pipe dream. And I don’t mean pipes filling with dried leaves of the medicinal sort.
At this point, we need to focus on the word ‘effective’.
‘It’s relatively easy after months (not weeks) of intensive training to turn out high-quality polygraph examiners. The difference lies in the trust built up between the operator and the interviewee, and the formulation of questions,’ Dreyer says.
‘What wasn’t appreciated in South Africa when polygraph testing was launched was the impact of culture on the outcome of polygraph tests. Tests can have only three outcomes – deception indicated, no deception indicated or inconclusive. Polygraph tests of interviewees of African descent consistently tested inconclusive when the tests were first introduced.’
Dreyer says polygraph examinations rely on measuring the physiological responses, such as movements of involuntary and heart rate, induced by the stress that should be caused by deception.
‘The examiner must have all the information about the incident about which the examinee will be questioned. The site of the incident must be visited. Then the examiner must draw up the test questionnaire and discuss the questions with the examinee.
‘Only the guilty person (or guilty people) will retain the memory of the incident being examined. The success of the test hinges on the reactions of the examinee to the questions being posed about an incident.
‘The concept of applying a polygraph test is to access information from a person’s memory. Everything that you see, hear or do is in your memory. The easiest way to access that information is to ask. The response is either the truth or not the truth.’
Dreyer’s experience in the field of forensic psycho-physiology came to the fore in addressing the cultural issues impacting the physiological responses of examinees.
‘It became clear that the type of questions that had to be asked and answered had to differ between people of different cultures. In African culture, the locus of responsibility lies outside the body. So in posing a question, the interviewer does not ask: “Did you do it?” Rather, the question would be: “Did you see who did it?”’
Citing an example of the need to adapt the form in which questions are asked, Dreyer said she was called to conduct a polygraph test at a Mpumalanga gold mine a few years ago. The questionee was a long-serving mine employee who had been tested eight or nine times but had passed each test. Despite his relatively low-earning job he lived in a luxurious house and owned several expensive motor vehicles.
‘I spent time going over the questions with the employee, gained his confidence and then ran the test. The employee answered all the questions truthfully and admitted he was enjoying the benefits of the theft of gold from the mine.’
Dreyer said it emerged from the employee’s answers that at no stage did he steal gold, take stolen gold to sell, or was handed money from gold that he had delivered to a purchaser. However, he had briefed others to undertake those tasks. He received money indirectly from the sale of gold stolen and sold by others.
‘If your eyes didn’t see gold being stolen, your hands didn’t take the stolen gold to a purchaser, or your hands didn’t receive the money from the purchaser who bought the gold, then you answer truthfully and pass the test. If the question is put differently: “Did you receive money from the sale of gold stolen from the mine?” and you answer negatively, then you fail the test. Questions put this way go directly to the issue of the locus of responsibility.’
Dreyer said she abandoned running polygraph operator tests as she felt guilty because as a result of breaking the trust she had engendered in interviewees when their test responses showed they were untruthful. She’d then have to testify against them at a disciplinary hearing.
- In terms of the South African Constitution, no one can be compelled to undergo a polygraph test. No legislation controls the use or abuse of the examination. Among the government departments that require employees to undergo polygraph tests are the military and the police, although the latter abandoned the use of the tests for a while. Banks, security companies and some retail businesses use polygraph tests.
- According to Justicia Investigations, the administering of polygraphs has ‘often led to the perpetrators confessing to their offences’.
- polygraph machines measure the chest activity by using pneumographs around the chest and the abdomen. Cardiovascular activity is measured by a blood pressure cuff. Electrodes attached to the fingertips test for perspiration indicated by the electrical conductivity of the skin.
