Canada: Only "Litigation Experts" Must Comply With The Expert Report Rules

Last Updated: June 9 2015
Article by Darcy R. Merkur

While 'litigation experts' hired by a party to a lawsuit must comply with the comprehensive expert report rules set out in rule 53.03 of the Ontario Rules of Civil Procedure, 'participant experts' like treating health practitioners and non-party experts like those hired by a non-party insurer need not comply with rule 53.03 in order to provide expert opinion evidence at trial, according to the Ontario Court of Appeal in their pragmatic and much anticipated decision in Westerhof v. Gee et al (2015) ONCA 206 (OCA), released on March 26th.

In Westerhof, the Ontario Court of Appeal determined that experts involved for reasons unrelated to the litigation are not caught by the expert report rules as they were not "engaged by or on behalf of a party". As a result, plaintiff's personal injury lawyers may now return to the customary, economical and sensible practice of relying on expert opinions from treating health practitioners actively involved in the care and treatment of an accident victim, without obligating the treatment provider to write a thorough rule 53.03 compliant expert report.

The Westerhof appeal dealt with the use of expert opinions that were not formally set out in a rule 53.03 compliant expert report. At trial, the trial judge had restricted expert opinion evidence from various treatment providers called by the plaintiff, including opinion evidence relating to the patient's history, diagnosis and prognosis, on the basis of technical non-compliance with rule 53.03. After a jury outcome that was unsatisfactory to the plaintiff, the plaintiff appealed to the Ontario Divisional Court. The Ontario Divisional Court dismissed the appeal and upheld the trial judge's decisions relating to the inadmissibility of the opinions from various treatment providers. The Ontario Divisional Court distinguished evidence from a 'fact witness' to evidence from an 'expert witness' and concluded that experts called to provide opinions, as opposed to factual evidence relating to their observations and treatment, must comply with rule 53.03.

On further appeal by the plaintiff with leave, the Ontario Court of Appeal disagreed with the ruling and distinctions made by the Ontario Divisional Court. Instead, the Ontario Court of Appeal emphasized and relied on the wording of rule 53.03 and its express reference to experts 'engaged by or on behalf of a party'.

In Westerhof, the Honourable Madam Justice Janet Simmons, writing for the Ontario Court of Appeal, concludes that only 'litigation experts' (those retained by a party to the litigation) qualify as experts 'engaged by or on behalf of party' within the meaning of rule 53.03. Justice Simmons distinguishes 'litigation experts' from 'participant experts' (such as doctors and other health practitioners involved in the treatment and care of a patient) and from non-party experts (such as experts involved by an insurer in the course of a statutory accident benefit claim or other disability claim). Justice Simmons rules that 'participant experts' and 'non-party experts' are not 'engaged' by a party and are therefore not subject to rule 53.03.

After reviewing the origins of rule 53.03, Justice Simmons comments as follows:

"....I see no basis for concluding that rule 53.03 was intended to apply to persons other than expert witnesses 'engaged by or on behalf of a party to provide [opinion] evidence in relation to a proceeding'." (see paragraph 81)

In disagreeing with the suggestion that any witness called by a party at trial has been 'engaged' by that party, Justice Simmons states:

"A party does not 'engage' an expert 'to provide [opinion] evidence in relation to a proceeding' simply by calling the expert to testify about an opinion the expert has already formed." (see paragraph 82)

It appears that Justice Simmons felt that treatment providers were different from 'litigation experts' as their opinions were often formed in advance of any litigation and were generally formed without regard to any ongoing litigation. For example, Justice Simmons writes:

"Unlike an expert witness engaged by or on behalf of a party to provide opinion evidence in relation to the proceeding, participant experts and non-party experts do not testify because they are paid an expert's fee to write the report contemplated by rule 53.03. Rather, they testify because they were involved in underlying events and, generally, have already documented their opinions in notes or summaries that do not comply with rule 53.03." (see paragraph 86)

Justice Simmons goes on to clarify that participant experts may give opinion evidence for the truth of its contents without complying with rule 53.03, where:

  • "the opinion to be given is based on the witness' observation of or participation in the events at issue; and,
  • the witness formed the opinion to be given as part of the ordinary exercise of his or her skill, knowledge, training and experience while observing or participating in such events." (see paragraph 60)

When it comes to experts retained by non-parties, such as experts retained by insurance companies as part of an accident benefit claim or a disability claim, Justice Simmons similarly concludes that these non-party experts need not comply with rule 53.03. Justice Simmons states:

"...I conclude that rule 53.03 does not apply to the opinion evidence of a non-party expert where the non-party expert has formed a relevant opinion based on personal observations or examinations relating to the subject matter of the litigation for a purpose other than the litigation." (see paragraph 62)

In support of the court's reasoning, Justice Simmons voices practical and economic justifications for not requiring treating health practitioners to comply with rule 53.03. Justice Simmons explains that:

"Requiring participant witnesses and non-party experts to comply with rule 53.03 can only add to the cost of the litigation, create the possibility of delay because of potential difficulties in obtaining rule 53.03 complaint reports, and add unnecessarily to the workload of persons not expecting to have to write rule 53.03-compliant reports (e.g. emergency room physicians, surgeons and family doctors)." (see paragraph 86)

Plaintiff's personal injury lawyers are elated with the decision since it allows crucial treating health practitioners to provide valuable and informed opinions without the need to prepare a comprehensive formal expert report. All too often, plaintiff's personal injury lawyers have faced resistance from treating health practitioners unwilling to spend the time preparing a detailed rule 53.03 compliant report, forcing the lawyer to retain alternative litigation experts at a considerable and seemingly unnecessary expense.

However, to the dismay of plaintiff's personal injury lawyers, the Westerhof decision opens the door to defence counsel calling non-party experts, such as medical experts hired by an accident benefit insurer or by a long term disability insurer, as expert witnesses at trial without the need for compliance with rule 53.03.

Of course, the Ontario Court of Appeal reiterates that the trial judge still retains the gatekeeper function regarding the admissibility of all evidence including opinion evidence and could limits its use or refuse its admissibility. And, in addition, Justice Simmons cautions against any attempt by a participant expert or non-party expert to provide opinion evidence beyond the scope of an opinion formed in the course of treatment or observation for a purpose other than the litigation by advising that in such circumstances the court could require formal compliance with rule 53.03.

In the end, the Ontario Court of Appeal allows the appeal and orders a new trial for Mr. Westerhof.

As a result of the Westerhof decision plaintiff's personal injury counsel now have confirmation that they can illicit vital expert opinion evidence at trial from key treating health practitioners without pressing such providers for a formal rule 53.03 compliant expert report.

The Westerhof decision will help reduce the cost of litigation and will ensure that the best evidence is made available to the trier of fact.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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