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Court of Appeal highlights ongoing gatekeeper role of trial judge in relation to expert evidence

In Bruff-Murphy v. Gunawardena, 2017 ONCA 502, the Ontario Court of Appeal emphasized the importance of the ongoing role of a trial judge as a gatekeeper, even after an expert is qualified to testify. In this case, the trial judge identified concerns that the expert witness crossed the line from an objective witness to an advocate for the defence. However, the trial judge did not exclude the opinion evidence or alert the jury about the problems with the witness’s testimony. As a result, the fairness of the trial was irreparably compromised. The Court of Appeal allowed the appeal and ordered a new trial.

The appellant was hit from behind by the respondent while stopped in her car. The respondent admitted liability and the sole issue in the 23 day jury trial was what damages, if any, the appellant suffered.

The appellant alleged that as a result of the accident she suffered soft tissue damage in her neck, lower back and right shoulder. In addition, the appellant alleged that the accident left her in a chronic pain condition with attendant anxiety and depression. At trial, the appellant called a number of physicians who testified that she suffered in the manner complained of and the cause of her suffering was the motor vehicle accident. The defence called two medical experts who had been retained to conduct independent medical examinations. The medical expert in question on appeal was Dr. Monte Bail, a psychiatrist.

At trial, counsel for the appellant objected to Dr. Bail’s testifying on the grounds that Dr. Bail’s report was essentially an attack on the appellant’s credibility and that Dr. Bail was biased. The trial judge ruled that Dr. Bail could not testify on certain sections of his report, primarily where Dr. Bail was critical of the reliability of the conclusions reached by other doctors who had examined the appellant. The trial judge also warned Dr. Bail against testifying about the appellant’s credibility.

Dr. Bail testified that his methodology was not to review medical records until after the examination. In this case, Dr. Bail met with the appellant for an hour, and subsequently spent 10 to 12 hours reviewing the appellant’s medical records, noting discrepancies between what she had told him and her medical records. A large portion of Dr. Bail’s report consisted of these discrepancies, which he never questioned the appellant on.

In summary, Dr. Bail’s evidence was that the appellant did not develop any psychiatric disorders or limitations as a result of the accident and required no psychotherapy or psychotropic medication in relation to the accident. In addition, Dr. Bail testified the appellant’s pre-accident psychiatric profile was not exacerbated by the accident and she did not require housekeeping or attendant care as a result of any psychiatric condition.

The Verdict

After the closing submissions, the trial judge delivered his charge to the jury, which had been previously reviewed at a conference by the parties. No objection was made to the charge and no special instructions regarding Dr. Bail’s testimony was requested. The trial judge reviewed Dr. Bail’s testimony briefly, but did not instruct the jury regarding the duty of expert witnesses or raise any concerns about Dr. Bail’s testimony.

The jury assessed general damages at $23,500 and rejected all other heads of damages claimed.

The Court of Appeal applies White Burgess

Although the trial judge was highly critical of Dr. Bail’s evidence, he allowed Dr. Bail to testify due to the very high threshold established by the Supreme Court in White Burgess Langille Inman v. Abbott and Haliburton Co., 2015 SCC 23. In White Burgess, released shortly before the judgment under appeal, the Supreme Court of Canada held that the basic structure for the law relating to the admissibility of expert evidence has two main components. The first component requires the court to consider the four traditional “threshold requirements” for the admissibility of evidence established by the Supreme Court of Canada in R. v. Mohan, [1994] 2 SCR 9, being (i) relevance, (ii) necessity in assisting the trier of fact, (iii) absence of an exclusionary rule; and (iv) the need for the expert to be properly qualified.

The second component is a “discretionary gatekeeping step” where the “the judge balances the potential risks and benefits of admitting the evidence in order to decide whether the potential benefits justify the risks”. In White Burgess, the court held the lack of independence or impartiality on the part of an expert witness goes to the admissibility of the witness’s testimony, not just to its weight.

In this case, the Court of Appeal held the trial judge erred in principle by failing to exercise this discretionary gatekeeper role. Instead, he appears to have believed that he was obliged to qualify Dr. Bail once he concluded that the witness met the Mohan threshold. On a proper balancing, the Court of Appeal concluded that the potential risks of admitting Dr. Bail’s evidence far outweighed its potential benefit. In addition to the troubling methodology used by Dr. Bail, the Court held that Dr. Bail viewed his primary role as to expose inconsistencies and not to provide a truly independent assessment of the appellant’s psychiatric condition. The task of comparing records to expose inconsistencies is a task for trial lawyers preparing for cross examination, and as the largest portion of Dr. Bail’s report consisted of identifying such inconsistencies, the Court of Appeal found his report to offer little probative value.

The court reviewed the steps the trial judge should have taken. Most importantly, the Court cautioned that a trial judge must continue to exercise his gatekeeper function even after the qualification stage. When the eventual testimony of an expert justifies any concerns of impartiality raised during the qualification stage, the trial judge must recognize the acute risk to trial fairness. At this time, the trial judge must take action. The general residual discretion to exclude evidence whose prejudicial effect is greater than its probative value is always available to the court.

In this case, a mid-trial or final instruction that Dr. Bail’s testimony would be excluded in whole or in part would have been appropriate. Alternatively, the trial judge could have asked for submissions from counsel on a mistrial, in the absence of the jury, and ruled accordingly. Although counsel for the plaintiff at trial did not seek instructions regarding Dr. Bail’s evidence, the Court of Appeal held the admission of Dr. Bail’s testimony resulted in a miscarriage of justice so as to warrant a new trial.