The insight that expert witnesses bring to courtrooms and tribunals can be invaluable in helping reach informed decisions. But there are definite rules governing who these experts can be and the scope of their testimony. That is why I was happy to see that the College of Physicians and Surgeons of Ontario (CPSO) recently approved a policy outlining what it considers to be appropriate regarding reports and testimony from expert witnesses. The advice given is relevant to other professions across the province.

The CPSO policy makes it clear that before a physician accepts a request to act as an expert witness they must disclose any perceived or potential conflicts of interest. This is good advice for any professional asked to appear in front of a tribunal or court.

Potential conflicts include having a personal or professional relationship with one of the parties involved. The expert must disclose if they have an interest, whether professional or personal, in the outcome of the case. Even if there is such a relationship, it may be possible to proceed if it can be shown that all parties are aware of the conflict and it will not affect the impartiality of the witness. However, allowing an expert to provide evidence in the face of a conflict, is rare.

The CPSO policy makes it clear that doctors are not obligated to act as a medical expert for a third party. Indeed, the participation of a professional as an expert witness at any tribunal must be voluntary.

Another key piece of guidance from the CPSO is the direction that the role of an expert witness is “to provide information and/or opinions for the third party … not to decide how the information and/or opinions will be used.” I agree. An expert witness is being asked for their learned opinion about a matter that falls in their area of expertise. After that has been given, it is up to the tribunal or court to decide if and how that opinion will affect the outcome of the case.

Developing reports and giving testimony takes time and effort so expert witnesses deserve adequate remuneration. The CPSO document directs members to its rules and regulations governing this work and I would recommend that members of other regulated professions have a look at their own policies.

Every profession can benefit from CPSO advice on writing third-party reports and testimony, as it instructs members to produce material that is “fair, objective, and non-partisan” while using “language and terminology that will be readily understood by the audience.

“Physicians must take reasonable steps to obtain and review all relevant clinical information and opinions relating to the subject that could impact their statements and/or opinions,” the policy directs, adding they “must not deliberately leave out relevant information and/or opinions in any third-party medical reports [or] make any unrelated or unnecessary comments.”

Wise words indeed. Technical jargon and terms that only insiders will understand must be kept to a minimum with any expert witness testimony or report.

“An expert is there to give an opinion. And the opinion more often than not will be based on second-hand evidence.”

The Supreme Court of Canada (SCC) has also weighed in on the topic of expert witnesses. In a 1982 decision, Justice Brian Dickson commented on the role expert witnesses play in the trial process, noting: “An expert’s function is precisely this: to provide the judge and jury with a ready-made inference which the judge and jury, due to the technical nature of the facts, are unable to formulate.

“An expert witness, like any other witness, may testify as to the veracity of facts of which he has first-hand experience, but this is not the main purpose of his or her testimony,” he continued. “An expert is there to give an opinion. And the opinion more often than not will be based on second-hand evidence.”

Two years later, Justice John Sopinka added this advice about expert witnesses in a SCC judgment. “Expert evidence, to be necessary, must likely be outside the experience and knowledge of a judge or jury and must be assessed in light of its potential to distort the fact-finding process,” he wrote. “The possibility the evidence will overwhelm the jury and distract them from their task can often be offset by proper instructions … the evidence must be given by a witness who has shown to have acquired special or peculiar knowledge through study or experience in respect of the matters on which he or she undertakes to testify.”

Those being asked to provide expert witness reports or testimony, or regulators seeking guidance about retaining these experts, are welcome to contact me at Siskind Doyle LLP for more information or guidance. Our firm has the trust and respect of a broad network of regulators and we want to help professionals find the legal solutions that work best for them.


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