The apex court recently issued a warning about something judges do routinely but is seldom commented upon.
The Court of Appeal warned judges against relying too much on witness demeanour to detect lying. The warning came in its written grounds for overturning a High Court decision granting an investment firm's claim to $1 million in dividends.
How much store should a judge set by witness demeanour in making a decision? This has serious ramifications in a criminal case where a guilty verdict can see the accused jailed or caned.
While "appearance" means the outward aspect, "demeanour" refers to how one acts towards others, consciously or not. The demeanour includes one's facial expressions, eye contact, gestures, tics and body language.
Little has been said on how judges should deal with witness demeanour. Perhaps we trust judges to use cold logic in following the rules of evidence and courtroom procedures, by which they draw rational conclusions from the evidence to reach a correct and just decision. Even judges may believe this about themselves as impartial assessors of fact who look only at the evidence presented on the witness stand.
But even if the rules of evidence and courtroom procedures might be adhered to assiduously, the courtroom is not a sterile operating theatre where a case is dissected with surgical precision.
Rather, it is reality theatre where participants play their assigned roles for the judge to determine guilt (in criminal cases) or fault (in civil cases). That is why demeanour matters, for the judge cannot help but notice it. Being human, judges are prone to being influenced by perceptions, no matter how hard they try to be objective.
Clearly, what lawyers say in court and whether they deliver it convincingly matter in the outcome of a trial; similarly, a witness' verbal and non-verbal behaviour, mannerisms, dressing and speech. Even spontaneous reactions in the gallery or the presence of the victim's family can add colouration to one's perception of truth.
So, what may not be formal evidence could still affect a trial's outcome, although judges are expected to assess such non-testimonial "evidence" judiciously.
But law professors tend to argue that demeanour should not be considered as it gives rise to the potential for prejudice, unless witness conduct in court is so brazen that no one can miss it.
In the early 1990s, based on research in psychology dating from the 1960s, a consensus emerged in the legal academy that observing demeanour is, at best, inaccurate and, at worst, useless for assessing credibility and culpability.
That older research found that people who used demeanour cues to detect lies were accurate only half the time. However, more nuanced studies recently show different results.
First, they affirm that demeanour cues by themselves indeed do not help detect deception.
For example, cues believed by many to show lying such as gaze aversion, speech pauses, blinking, smiling and fidgeting, in fact, are not linked to deception at all.