Tuesday, 5 November 2013
Conflicting Expert Evidence: Two Is Better Than One
Conflicting expert evidence often reflects a genuine difference of professional opinion within the expert’s field. Just as two separate Courts may make different interpretations of the same expert evidence, so too may two different experts make conflicting opinions based on a single fact. In several Malaysian and Singaporean case, we can find various opinions and legal rulings on how to treat two conflicting expert evidence.
In the case of Chua Seng Sam Realty Sdn Bhd v Say Chong Sdn Bhd & Ors And Other Appeals, His Lordship Mohd Hishamudin JCA opined that, in treating conflicting expert evidence, the court, besides examining the credibility of the experts, should also examine the scientific grounds and facts relied by the experts and whether, when taken in totality, the inferences drawn from their findings are sound or otherwise.
Then, in the case of Cheong Fatt Tze Mansion Sdn Bhd v Hotel Continental Sdn Bhd, His Lordship Vincent Ng Kim Koay J (as he then was) said at page 364 as to treatment of conflicting expert evidence as follows: “As there is conflict in expert evidence, the court's approach in evaluating such conflicting evidence besides evaluation of credibility is not only to examine the scientific grounds and basis on which they rely, but also in my view, if one of the experts is involved in the impugned-works (as here), the court may examine the manner in which he had implemented the proposed works as an engineer.
Then, in the case of Singapore Finance Ltd. v Lim Kah Ngam (Singapore) Re. Ltd. & Eugene HI. Chan Associates (Third Party), it was held inter alia that the court's approach in evaluating the conflicting expert's evidence is to examine the scientific grounds and bases, on which they rely. Where the opinion of an expert is based on reports of facts and empirical observations, the court has to satisfy itself, on a balance of probabilities, whether those facts did in truth exist and whether any inference or inferences drawn from those facts taken individually or collectively, were sound or not.
Then, in the case of Sakthivel Punithavathi v Public Prosecutor, the court outlined in length the approach which should be adopted by the courts in dealing with conflicting expert evidence. Generally speaking, the court should scrutinize the credentials and relevant experience of the experts in their professed and acknowledged areas of expertise. Not all experts are of equal authority and/or reliability. An expert with relevant clinical experience may often prove to be more credible and reliable on "hands-on" issues.
Then, the court must look into the academic credentials of that particular expert, as it may sometimes be relevant for determining the weight of his evidence since it gives an indicator of an expert's familiarity with the subject. That having been said, it is not the sole determinant for choosing between the conflicting opinions of experts. After all, an expert need only be skilled and it is trite law that such skill can be acquired either by special study or experience.
Besides, in resolving conflicting expert opinions, it is often far more productive to look at other considerations such as the methodology by which an expert has reached his or her conclusions and the demeanour of the expert, rather than merely comparing the pedigree of their curriculum vitae (Leong Wing Kong v Public Prosecutor).
Furthermore, once a judge has weighed the conflicting opinions and reached a conclusion as to which opinion he prefers, it is a finding of fact which an appellate court would be loathe to disturb unless there are compelling grounds to do so (Muhammad Jefrry v Public Prosecutor).
In conclusion, to put it in simple way, the court is bound to critically scrutinize all the evidence given by experts, and in circumstances where there are two conflicting opinions and findings, the court is in its best position to opt the better of two conflicting opinions. Like Dato' V.T. SIngham J once said, "The court’s duty is not to become an expert but to verify the opinion of the expert" ((Nik Mahmood Bin Nik Mat v Chew Kam Leong).