THE ROLE OF AN EXPERT WITNESS
In Bharat Forge Ltd v Bombardier Aerospace Services Singapore Pte Ltd [2022] SGHC 179, the High Court considered the opinion of the plaintiff’s expert, and ultimately found that the expert opinion was not of any assistance. The High Court also stated that it “was unconvinced by the pro-[plaintiff] views that [the plaintiff’s expert] put forward” (at [81]). This decision serves as a timely reminder on the expectations of an expert witness.
In litigation, an expert’s evidence is subject to requirements under the Rules of Court, be it under the old Rules of Court (Cap. 322, R 5, 2014 Rev. Ed.) (“Rules of Court 2014”) or under the new Rules of Court 2021. For example, an expert’s duty to assist the Court on matters within his expertise remains unchanged whether under the Rules of Court 2014 or Rules of Court 2021, and this duty overrides any obligation owed to the person from whom the expert receives instructions or by whom the expert is paid.
The case. In Bharat Forge Ltd v Bombardier Aerospace Services Singapore Pte Ltd, the plaintiff (“Bharat Forge”) sent its second-hand Bombardier Global XRS business jet to the defendant (“BASS”) for a maintenance check and for the installation of a new cabin management system (“CMS”) (at [2]).
After the aircraft was returned by BASS to Bharat Forge, Bharat Forge complained about various alleged defects with the aircraft (at [3]), leading to the suit in question.
Instructed to assume defects existed. Bharat Forge’s sole factual witness (“Mr Thakre”) only had personal knowledge of one of the defects Bharat Forge had complained of (at [4] – [6]). However, Bharat Forge’s only other witness, its expert (“Mr Martin”), was instructed to assume that the defects alleged by Bharat Forge existed, which he duly did, thus leaving the primary question of whether the alleged defects existed to factual evidence (at [6]; [71]).
In this respect, the High Court stated that “Mr Martin’s expert report dealt only with the secondary question: assuming the alleged defects existed, was BASS responsible for them?” (at [6]; emphasis added by the High Court)
We pause here to observe that the framing of the issues for an expert to consider is very important. For example, an opinion sought to ascertain if defects existed may be very different from an opinion sought to critique solely on whether the repair methodologies proposed are reasonable on the premise that defects existed.
Instructions. Returning to the case, in assessing the scope of Mr Martin’s instructions, it was discovered that Mr Martin had never received the solicitors’ letter (exhibited to his Affidavit of Evidence-in-Chief (“AEIC”)) which purported to set out the instructions on which Mr Martin gave his expert opinion (at [74]).
In fact, Mr Martin had affirmed his AEIC with just its text and cover pages for the exhibits, but without exhibits (at [72]).
The High Court held that given the above facts, “[a]ll this makes a mockery of the process of an expert witness affirming an affidavit which confirms on oath his expert opinion, and the basis on which it is given.” (at [75])
Expert witnesses should bear this criticism in mind and ensure that they carefully review their report before signing. This includes ensuring that documents which form part of their report have been properly annexed or exhibited (as the case may be). It is a requirement under both the Rules of Court 2014 and Rules of Court 2021 that expert evidence must be given in a signed report which is exhibited in an affidavit made by the expert. This is extremely important and should be complied with, in substance and in form.
Expertise. While Mr Martin “relied on having attended courses and obtained certificates from [the courses]”, the High Court was concerned that “these were short courses of between two to five days, and did not relate to the carrying out of maintenance work or CMS installation work.” (at [77])
After assessing Mr Martin’s experience and qualifications, the High Court found that “Mr Martin lacked the necessary knowledge to be an expert on the causes of the Defects – which is what he was asked to give an expert opinion on.” (at [76] – [77])
In fact, Mr Martin admitted at trial that he did not know the cause of various defects (at [79]).
Section 47(2) Evidence Act 1893 defines an expert as a person who has “scientific, technical or other specialised knowledge based on training, study or experience” (at [76]). This definition has been echoed in the Rules of Court 2021 (see Order 12 Rule 1).
While it may not always be strictly necessary for the expert to have, e.g., professional qualifications (though, of course, this depends on the particular matter of expertise the expert’s opinion is being sought for), it must be borne in mind that a common issue that frequently arises during the hearing is whether the expert is suitably qualified to serve as an expert. Therefore, parties should ensure that their experts are indeed suitably qualified.
Documents. The High Court also found that “Mr Martin did not review the documents provided to him so as to offer a considered opinion” (at [78]). In fact, Mr Martin admitted on several occasions that he was seeing certain documents for the first time (at [78]).
The High Court further found that “… [t]his cursory approach permeated Mr Martin’s report. For instance, his “view and assessment” of each of the 12 CMS Installation Work Defects was word-for-word the same: it was just copied and pasted, with no specific analysis of individual Defects.” (at [79])
The High Court was also of the view that Mr Martin, having done a forensic audit of the aircraft earlier in 2019, “… ought properly to have disclosed this earlier involvement with the very aircraft that he was providing an expert opinion on.” (at [80])
As an expert professes as to opinions and not facts, it is important to understand what are the facts and assumptions (if any) relied upon by the expert in reaching his opinion. The Rules of Court 2021 sets out clearly that the expert’s report must include the agreed or assumed facts as well as a list of the materials that the expert relied on (see Order 12 Rule 5(2)(c) – (d)).
Takeaways. This decision serves as a timely reminder of the role of an expert witness, including considerations in instructing an expert and what an expert should (or should not) do. Among others:
Expert’s brief. The expert’s brief sets out what the expert has been asked to opine on. It should therefore be carefully framed to set out the specific issues the expert has been asked to deal with. Further, the expert’s report should clearly set out what are the specific issues the report addresses (or has been asked to address).
Expertise. Before engaging an expert, carefully consider whether the potential expert has the requisite expertise on the relevant subject matter. This will include issues such as, e.g., if the expert is qualified by dint of academic qualifications alone, or if the expert is qualified due to his experience working in the relevant industry, and which type of qualifications is more relevant and appropriate for the dispute at hand.
Documents and Facts. As an independent and impartial witness, an expert should also consider (and check) if he / she has gone through all the relevant documents, and if it is necessary to ask for more documents. The expert should also check and ascertain if the report has set out clearly what are the agreed and assumed facts, and if the report has clearly set out the relevant documents the expert is relying on.
While we have, thus far, discussed this in context of domestic litigation under the Rules of Court, these considerations are, we would respectfully suggest, of general application, and the parties should bear them in mind whenever the issue of expert witness arises.
This publication is not intended to be, nor should it be taken as, legal advice; it is not a substitute for specific legal advice for specific circumstances. You should not take, nor refrain from taking, actions based on this publication. Chancery Law Corporation is not responsible for, and does not accept any responsibility for, any loss or damage that may arise from any reliance based on this publication.