Focus: Use of expert witnesses under scrutiny

In the nearly two years since the Supreme Court of Canada set out a framework to assess the independence of expert witnesses, there has been an increased spotlight on this kind of evidence, and subsequent lower court decisions have stressed the importance of a judge’s gatekeeper role in this area.

Where there remains a difference of opinion among litigators though is whether it is too difficult to exclude the evidence of expert witnesses altogether on the basis of bias.

“It is very hard to get it excluded,” says Linda Matthews, a partner at Matthews Abogado LLP in Toronto.

Gradually, though, this may change as trial court judges pay more attention to the backgrounds of expert witnesses, suggests Matthews, who practises in the insurance litigation field.

“If counsel presents it in the proper way, I think these arguments [to have experts ruled inadmissible] will be more persuasive,” she says.

The Supreme Court’s ruling in White Burgess Langille Inman v. Abbott and Haliburton Co. in April 2015 stated that expert evidence may pose “special dangers” and courts must ensure that basic standards are met before the testimony is admitted.

The decision, written by Justice Thomas Cromwell, stated an expert’s first duty is to the court and to be fair, objective and non-partisan.

The obligation to be independent is to be considered for admissibility, as well as weight, said the Supreme Court.

However, it explained that the threshold for admissibility will usually be met.

“Once the expert attests or testifies on oath to this effect, the burden is on the party opposing the admission of the evidence to show that there is a realistic concern that the expert’s evidence should not be received because the expert is unable and/or unwilling to comply with that duty,” wrote Cromwell.

Since that decision was released, the Ontario Court of Appeal has applied the White Burgess principles on at least two occasions.  

“The decisions on whether a witness is biased, and whether to accept expert evidence, are quintessentially within the trial judge’s mandate,” the appellate court stated in Froehlich-Fivey v. Fivey, a ruling issued last November.

In its ruling last fall in R v. Shafia, the Court of Appeal said that expert opinion evidence must first satisfy the test established more than 20 years ago in R v. Mohan of relevance, necessity, absence of an exclusionary rule and qualifications.

If an expert is found to be impartial, a second gatekeeping step must be followed, which involves the trial judge balancing potential risks and benefits of admitting the evidence.

“The inquiry is equally case-specific. It involves the exercise of judicial discretion, not the application of a bright line rule,” wrote Justice David Watt for the Court of Appeal.

The role of experts in both criminal and civil litigation is continually being refined by the courts, suggests Daniel Reisler, a founding partner at Reisler Franklin LLP in Toronto.

“There is a lot of attention being paid to the use of experts,” he says.

While the fundamental rules about the use of expert evidence are not dramatically different from what the Supreme Court said in 1994 in Mohan, there appears to be a greater tendency for plaintiffs, especially in personal injury litigation, to allege that a defence expert is biased, he says.

The appropriateness of this “needs to be clarified,” says Reisler, who primarily represents defendants in civil proceedings and is a past president of the Canadian Defence Lawyers organization.

In a decision issued last year on a threshold motion in a civil jury trial, a Superior Court judge expressed regret for having permitted a doctor to testify as a defence expert, in a case where Reisler was counsel for the defendant.  

Justice Paul Kane referred to “the very high threshold” to exclude an expert for bias under White Burgess. At the same time, the judge stated that he would not qualify witnesses in the future who presented the same approach to their testimony.

The jury awarded a modest amount of damages in that case, Bruff-Murphy v Gunawardena, and an appeal will be heard by the Court of Appeal this spring.

Without commenting on the specifics of the litigation, since it is before the Court of Appeal, an expert who comes to similar conclusions in more than one case is not necessarily biased, says Reisler.

“These are honestly held beliefs on issues that come up again and again,” he explains.

This is especially common in motor vehicle accident litigation, Reisler says.

At the same time, he says, it is crucial in the selection of an expert that the person really is an expert in their field.

“I have never gone out to find an expert to say what I want them to say. Finding the right expert means finding someone who is going to be straight with you,” says Reisler.

Matthews cautions against retaining experts who might testify too frequently in court and generate a large amount of their total income from this work.

“I look for experts who practise in their field, not just people who are expert at being experts,” she explains.

Insurance-based litigation is an area where expert evidence is very common, but the principles set out in White Burgess may also impact other areas, such as in aboriginal law cases, says Toronto lawyer Senwung Luk.

White Burgess is a reasonable and sensible approach” to dealing with the alleged bias of experts, says Luk, a partner at Olthuis Kleer Townshend LLP in Toronto.

There should be a low threshold for admissibility, especially in the aboriginal law field, and then it is up to the trial judge to determine the weight it is given, he says.

“There are different types of expertise and not always one right answer,” says Luk.

It is not uncommon for the federal government to allege an anthropologist is biased simply as a result of spending many years studying an indigenous community, he notes.

While aboriginal law litigation often takes years before a case is completed, Luk believes the long-term impact of White Burgess may be positive for indigenous communities in the use of experts in these cases.