Updated 07 September 2015

The state of ‘expert’ evidence in SA courts

CyberShrink questions the way in which expert witnesses are allowed to operate in South African courts.


The state of evidence presented to our courts by so-called expert witnesses is alarming. Some of these people are indeed experts, but are called on to testify on matters outside their actual field of expertise. 

Some, who are actual experts in the relevant field, hold eccentric or minority views, not shared by many of their colleagues. Others, again, are self-appointed experts, without any actual qualifications or recognition by colleagues, eager to share their opinions with the world.

This past month I was troubled by some of the evidence given by a psychologist in the DJ Donald Sebolai case, illustrating the problems caused by asymmetric use of experts. 


I’ve known Dr Saths Cooper for many years as a distinguished and honorable psychologist, but his evidence in the Sebolai case made me uneasy.   

Dr Cooper testified that the accused’s story of his girlfriend’s death was probably true, because he repeated the same story while under hypnosis. This should not have been permissible because, in most parts of the world, evidence obtained by or under hypnosis is not accepted or allowed to be presented in court.

Read: Can you trust your memory?

Hypnosis involves rendering the person very highly suggestible, to the point that they become likely to accept uncritically whatever is suggested to them. There isn’t a shred of evidence that statements made in a hypnotic state are in any way more likely to be credible and truthful than when made in an ordinary state of mind. Though hypnosis may increase the amount of accurate information recalled, it also increases the amount of inaccurate information “recalled” and reported. People can lie under hypnosis!

Another reason for serious concern is that he said the accused “was not even aware that he had been hypnotised at the time”. This is problematic because any health professional carrying out any procedure on anyone, whether administering a drug, conducting even minor surgery, or hypnotizing them, is required to get informed consent from the patient, which was clearly not possible if he wasn’t aware that he was being hypnotised.    

Assessing the whole case

When cross-examined by the prosecutor, Dr Cooper said he was confident in his techniques, but admitted they were not “fool proof”. There is also no indication what scientific research Dr Cooper used to support his various assertions

He was also challenged for having relied solely on his meetings with the accused and interviews with his sister and boss, and ignoring the contents of the docket and all evidence. He’s quoted as saying, “With all respect ma'am, my job is not to assess the case but to assess the state of mind of the accused. [Looking at the facts of the case] is the court's job.”

It is, however, is very much the expert’s job to assess the whole case as it reflects on the accused’s state of mind through the entire relevant period.  It’s impossible to properly assess that state of mind in an interview without knowing all available evidence that could be relevant. An expert who deliberately ignores available evidence and can’t relate his assessment to all the facts of the case is not a functional expert, or useful to any court. 

He was described as having taken the accused “back to the scene of the murder through hypnosis”, and being convinced that his version of events was truthful and probable. Truth is not something one can assign to any statement made under the influence of dissociation or hypnosis. 

Read: Going under

Cooper has been a leading figure in the Natal Indian Congress, the Black Consciousness movement, AZAPO, and other organizations, was a political detainee, and eventually Vice Principal of UDW, and even a Chairman of the Road Accident Fund. He has excellent qualifications in psychology, has been elected President of the Psychological Society of South Africa, and is an Honorary Professor of Psychology at the School of Social Sciences of the University of Limpopo.

Dealing with the need for expertise

The South African justice system is highly sloppy in how it deals with the need for expertise. By not adequately checking the qualifications of every one claiming to be an expert, and whether their theories can be taken seriously, is doing serious damage to its effectiveness, misleading and confusing courts and potentially leading to serious miscarriages of justice.    

Another problem is the unequal availability of experts. Most private citizens can’t afford to hire an expert, however much it might help their case. Rich defendants, however, can bring in as many experts as they wish (as in the Oscar Pistorius case). What makes the situation even more unbalanced is that prosecutors also can’t get the experts they really need for effective prosecution unless there’s someone available for free within the system. This means that they run the risk of losing long and expensive cases because they can’t get the expert advice and evidence they need.

Read: The Oscar Pistorius trial is super confusing

Why do we need experts? 

Under ideal circumstances all judges would be wise, well-educated and with a wide general knowledge.  This is however not how things are, and many criminal and civil cases involve essential technicalities which only experts in a particular field can understand, explain, and apply to the case.

But some experts forget their role and become hired mercenaries, fighting for whichever side’s paying them and treating their area of knowledge like a buffet, picking and selecting only those bits that suit them. This is why it is essential that both sides have access to expert advice, so that they can offer the court objective, balanced and accurate explanations.

When experts are bought

It’s commonplace that an expert feels pressure from the lawyers who involved him “to adapt his opinion towards the position most helpful to their case”.  If he is not to become a mercenary whose opinion is for sale, he must resist those pressures. I have noticed with distress how some “experts” express contradictory views in different cases, emphasizing different facts, and omitting others, depending on what is be most helpful to the legal team that hired them. Experts should be paid for their time and effort, but not their opinions. 

Dumani in his excellent analysis of such situations, wrote: “It is my view that expert witnesses who give  evidence of an opinion not generally held, could be guilty of perjury, while those who suppress relevant information may be guilty of obstructing the course of justice.“

Read more:

Ask your psychiatrist

What's wrong with psychiatry?

Introducing the International Academy of Hypnosis


Aspects of expert evidence in the criminal justice system. Msebenzi Dumani. Dissertation for Master of Law degree, Nelson Mandela Metropolitan University.    

Professor MA Simpson is Health24's CyberShrink. A South African psychiatrist, he qualified in medicine and in psychiatry in Britain. He has been a senior academic, researcher, and Professor in several countries. Read more of his columns.




Read Health24’s Comments Policy

Comment on this story
Comments have been closed for this article.

Live healthier

Exercise benefits for seniors »

Working out in the concrete jungle Even a little exercise may help prevent dementia Here’s an unexpected way to boost your memory: running

Seniors who exercise recover more quickly from injury or illness

When sedentary older adults got into an exercise routine, it curbed their risk of suffering a disabling injury or illness and helped them recover if anything did happen to them.