Rules governing Expert Witnesses in Personal Injury Claims

The amount of compensation and damages for which an accident victim is eligible is directly related to the severity of their injuries and their corresponding losses.  These losses may entail: income loss (past and future); medical, rehabilitation and attendant care expenses; housekeeping and home-maintenance expenses; out-of-pocket expenses for family members; and non-monetary losses such as a victim’s loss of enjoyment in life.  In any personal injury claim, proving the magnitude of one’s losses requires documentation and assessment from various experts, most particularly, from health care professionals.

Most personal injury lawsuits can be resolved through negotiation with the defending party and their insurer, and substantiating medical documentation must be presented to support the injured person’s claim.  A minority of cases — those that cannot be successfully resolved for the claimant through negotiation or arbitration – are brought to trial. In such cases, expert witnesses for the defendant and plaintiff typically give their professional and opposing opinions on the severity of the accident victim’s losses.  The outcome of cases often rests heavily on the strength and credibility of the medical opinion and witness testimony, and for this reason, it is very important that medical experts are qualified, objective and impartial in their assessments.  However a not uncommon complaint is that many experts are “hired guns” who tailor their reports to suit the needs of a client, such as those experts regularly retained by large insurance companies.

In Ontario, the Rules of Civil Procedure, RRO 1990, govern the duty of an expert witness.  The Rules specify that opinion evidence provided by the expert must be “fair, objective and non-partisan” and this requirement supersedes the expert’s obligations to the party on whose behalf they are testifying.  This rule was added in 2010, along with other significant changes made to the Rules, based on recommendations by the Honourable Coulter Osborne.  Another requirement is for full disclosure in the expert’s report, which must include a description of the factual reasons for the expert’s opinion, a description of research carried out by the expert that led them to their opinion, and a list of all documents referenced in forming the expert’s opinion.

Rule 53.03 of the Rules of Civil Procedure, added in 2010, defines several requirements for expert witness testimony, and Ontario courts may exclude testimony that does not comply with these rules.  Rule 53.03 stipulates information that must be included in an expert’s report, such as the expert’s name, address and area of expertise; his/her qualifications, educational experiences and employment; the instructions that were provided to the expert in relation to the proceeding; the type of opinion being sought for the proceeding; and the expert’s signed acknowledgement of his/her duty. However, in 2015, the Court of Appeal decided that rule 53.03 applies only to experts who have been engaged on behalf of the party to the litigation (i.e. litigation experts), but not to ‘non-party’ experts and ‘participant’ experts.  Non-party and participant experts are those experts who did not form their opinion for the purpose of litigation, but rather, their opinion is based on personal observations or assessments, such as are commonly gathered by a patient’s personal physician(s).

In 2015, the Ontario Court of Appeal was required to rule on a previous decision in a trial by jury, McCallum v. Baker, in which the plaintiff, Mr. McCallum was awarded damages of $787,275 for injuries that resulted from a motor vehicle accident when his car was rear-ended by Mr. Baker.   The defendant appealed the trial judge’s decision, arguing that the trial judge erred in permitting the claimant’s medical experts to give “an avalanche” of opinion evidence that went beyond the scope of their specific expertise and was not directly connected with the treatment of their patient, which is therefore in non-compliance of rule 53.03.  Some of the opinion evidence that the trial judge allowed to be presented concerned an assessment of Mr. McCallum’s future ability to work and his future requirements for rehabilitation and treatment.   However, the appeal judge agreed with the trial judge’s conclusion that because the expert witnesses in the McCallum trial were treating medical practitioners, they are entitled to present opinion evidence without conforming to rule 53.03.  Accordingly, the Ontario Court of Appeal dismissed Mr. Baker’s appeal and upheld the damages awarded in the jury trial.

In any personal injury action, the court assesses whether each expert who is providing opinion evidence in the case has the specific expertise or relevant authority to give an opinion on the subject matter and also, whether or not they are predisposed or biased in supporting one side or another.  The importance of utilizing qualified and credible experts in substantiating an injury claim cannot be over-stated; a credible expert can prove the legitimacy and magnitude of losses suffered by a claimant.  At Kotak Law, our connections with medical professionals in the community as well as our experience in building cases substantiated by solid medical evidence, are some of the reasons for our success in obtaining favourable compensation for our clients.  Call Kotak Law today to find out how we can help you in filing a successful claim.


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Disclaimer: This article is intended to supply general information to the public. We make every effort to ensure the accuracy of this information. However, as laws change quickly, the reader should always ensure the accuracy and applicability of such information with respect to their particular case. The information contained in this article cannot replace a thorough and complete review of the reader’s situation by competent legal counsel who has had an opportunity to review all of the facts.