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Who makes a Good Expert Witness

It is well known that an expert witness should be independent and owe his duty to the Court rather than the party appointing him. However, it is not uncommon that experts will tend to render their opinions in such a way as to best support the cases of the parties appointing them. Some experts go so far as to make themselves advocates for the parties and even opine freely on matters in which they do not have the requisite expertise.

In the recent Hong Kong case of Hong Kong Housing Authority v Hsin Yieh Architects & Associates Limited and others (2 September 2005; HCCT 39/2001), Mr Justice Reyes found that the engineering expert of one of the parties was "unduly defensive and obscure". It appeared to the Judge that this expert was attempting to put together some vague justification for the party appointing him. Another expert in the same case avoided answering questions on a particular point directly and when being pressed to do so, it became apparent that he was defending the party appointing him by relying on some unlikely" extreme" situation, to say the Counsel cross-examining him on the point could conceivably be wrong. The Judge was left with the impression that the expert was simply unwilling to admit to a straightforward error. The Judge made it express in his Judgment that the approaches taken by these experts undermined the confidence which he might otherwise have had in them as experts.

The Judge similarly made criticisms of the quantum expert giving evidence in the case for one of the parties. The Judge criticised the expert in question for giving views on a whole range of matters beyond his expertise or knowledge including opinions on the progress of works, the granting of extensions of time and the causation of certain reinstatement works. The Judge said that the fact that a quantity surveyor might routinely be asked (and remunerated) by employer or contractor for his views on matters of programming or causation does not render these views admissible in Court when the quantity surveyor gives quantum evidence. The Counsel representing the party tried to "save" the evidence of this quantum expert by suggesting that even if the quantum expert had made submissions on other issues, these submissions could be made by him (i.e. the Counsel) in any event and the Counsel went on to adopt expressly the points made by the quantum expert as his own submissions. The Judge pointed out that whilst Counsel is entitled to make submissions as he deems appropriate, the difficulty with an expert advancing "submissions" is that it would fatally undermine the expert's credibility as an impartial expert in the Court's eyes. The expert has become "no more than another advocate" of the party appointing him, which is the "the very thing which an expert is not supposed to be". The Judge again said he could not place much reliance or confidence on the expert's evidence.

In civil proceedings in Hong Kong, all one needs to do to win a particular issue or a case generally is to convince the Court that on a balance of probability, the evidence adduced in support of one party's case is more reliable than the opposing party's. The undermining of the Court's confidence in a party's witnesses will have disastrous consequences in respect of the issues their evidence relates to or the case generally. Not surprisingly, the evidence of the experts critcised by the Judge in the case was mostly rejected by the Judge and the party appointing them lost on the relevant points as a result, which also led to an overall adverse judgment against them.

In the case of Kin Shing Engineering (HK) Co Ltd v Vinson Engineering Ltd (15 April 2005; HCCT 108/2002), Mr Justice Reyes made a point about the effect of an experts' joint statement. In that case, the Counsel representing one of the parties was trying to reopen some of the issues stated in the joint statement of the experts. The Judge considered that in the absence of a supplementary report from the expert for the party stating that he had resiled from what he had agreed and explaining why, it was not open for the party to do so. The Judge also held that it would be unfair to allow a party to go back on what the parties had, through their experts, previously agreed. The parties must be bound by such agreement in the absence of a truly compelling reason. An expert therefore should consider carefully the points in question before agreeing them in a joint statement.

It can be seen from the above judgments that an expert should think carefully before agreeing issues. When giving evidence, he should focus on his area of expertise and avoid being an advocate and making submissions on behalf of the party appointing him. He owes his duty to the Court and should answer questions directly in order to assist the Court in understanding the various technical or expert matters. A partisan approach will not only be inappropriate but more importantly also undermine the Court's confidence in an expert's evidence thereby jeopardizing the party's case. It is not uncommon for parties to prefer experts who can be "persuaded" to advance their points. This approach may well be counter-productive and undermine the experts' credibility in the Court's eyes which is all the more important.

Lovells Newsletter
January 2006

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