“Expert witnesses are firmly part of Ontario’s justice system and have been so for several decades. Expert witnesses provide invaluable assistance for parties and the Court. Based on their unique expertise, they can assist in uncovering and analyzing relevant facts related to matters in dispute. They can advise parties on appropriate factual inquiries to make of the opposing party which can inform the expert’s opinion. Those opinions can assist parties in reaching settlement. An expert’s evidence can provide tremendous help to the trier of fact in understanding the facts and in making factual findings.
It can be fairly stated that with the proliferation of expert evidence, an industry of experts in various fields now exists. For example, in family law, the use of chartered business valuators, is now commonplace. They are very helpful in resolving family disputes, particularly ones involving litigants with business income or corporate assets.
With this proliferation of experts, there was a common complaint that too many experts were “no more than ‘hired guns’ who tailor their reports and evidence to suit the client’s needs.”: The Hon. Coulter A. Osborne, Report of the Civil Justice Reform Project: Findings and Recommendations (November 2007). In fact, this was a principal objective behind amendments to the Rules of Civil Procedure and the Family Law Rules, that introduced new duties on experts, and required expert witnesses to attest to those duties, namely to provide opinion evidence that is fair, objective and non-partisan: see r. 20.1(2) and (3), Family Law Rules.
The duty to provide objective and non-partisan opinions is one trait that distinguishes experts from lawyers, who advocate for one party’s interests and who are clearly partisan. The solicitor/client relationship, which is fiercely protected, is also manifestly different than the relationship between a party and a retained expert. As such, the ruling in MacDonald Estate v. Martin, 1990 CanLII 32 (SCC), [1990] 3 S.C.R. 1235, relied upon by the Respondent, is not dispositive.
In MacDonald Estate, a junior lawyer worked at a law firm for the appellant. He switched to a new law firm that acted for the respondent. The Supreme Court held that the respondent’s law firm was disqualified from acting for the respondent. It set a test to determine when a law firm is disqualified to act by reason of conflict of interest.
In McDonald Estate, the Court was concerned with three competing values that are unique to the practice of law, and not applicable or of negligible relevance to whether an expert witness should be disqualified to be a witness: the concern to maintain high standards of the legal profession and the integrity of our justice system; that a litigant should not be deprived of their choice of counsel without good cause, and; desirability of permitting reasonable mobility in the legal profession.
I accept that expert witnesses are sometimes engaged in litigation planning and can provide strategic advice to parties. In such a case, does the analysis of whether a conflict of interest exists for an expert witness elevate to that used for a lawyer?”