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Court of Appeal Clarifies Procedural Requirements for Admission of Expert Evidence in Ontario

12 minute read


Expert evidence is an integral part of almost every trial. Over the last decade, a number of trial judges and legal authors have raised concerns about the proliferation of expert evidence. The increased use of experts is generally considered to be a significant factor in the ever increasing costs of litigation and has become a very real access to justice issue. At the same time, legitimate concerns have been raised with respect to the reliability and quality of the expert evidence being tendered in court. In Ontario, at least two significant reports authored by respected jurists have examined these issues and made recommendations attempting to address them. In 2007, the Honourable Coulter Osborne released his review of the civil justice system in the report entitled Civil Justice Reform Project: Summary of Findings & Recommendations (the “Osborne Report”).[1] The second report was authored by the Honourable Stephen Goudge following his Inquiry into Pediatric Forensic Pathology in Ontario.[2]

In 2010 significant changes were made to the Rules of Civil Procedure[3] relating to expert witnesses. In particular, Rule 53.03 was amended to prescribe new time frames for the delivery of expert reports and to enumerate a list of requirements concerning the substance of an expert's report. In addition, Rule 4.1.01 sets out the duty of the expert to provide fair, objective and non-partisan evidence that relates only to matters within the expert's area of expertise. Most importantly, the amended Rule provides that the expert's duty to the Court prevails over any obligation owed to the party who engages the expert. While these duties were already well established by earlier jurisprudence, experts were now also required to acknowledge compliance by executing a Form 53.

These new procedural requirements no doubt flowed from the Osborne Report where it was noted:

The issue of “hired guns” and “opinions for sale” was repeatedly identified as a problem during consultations. To help curb expert bias, there does not appear to be any sound policy reason why the Rules of Civil Procedure should not expressly impose on experts an overriding duty to the court, rather than to the parties who pay or instruct them. The primary criticism of such an approach is that, without a clear enforcement mechanism, it may have no significant impact on experts unduly swayed by the parties who retain them.

An expressly prescribed overriding duty to provide the court with a true and complete professional opinion will, at minimum, cause experts to pause and consider the content of their reports and the extent to which their opinions may have been subjected to subtle or overt pressures. Matched with a certification requirement in the expert's report, it will reinforce the fact that expert evidence is intended to assist the court with its neutral evaluation of issues. At the end of the day, such a reform cannot hurt the process and will hopefully help limit the extent of expert bias.[4]

There has been considerable debate as to the scope of these new requirements and, in particular, whether they apply to all expert evidence or only to experts retained by the parties to the litigation.

The Court of Appeal recently released an important decision in Westerhof v Gee Estate[5] which will go a long way in settling this debate although a number of questions remain unanswered. While the decision in Westerhof was made in the context of two personal injury appeals – Westerhof v Gee Estate and McCallum v Baker – the principles flowing from the decision will have a wide application to all expert evidence.

Lower Court Decisions

Both Westerhof and McCallum were claims for damages arising from motor vehicle accidents. The trial judges in both actions were required to make rulings with respect to the admissibility of certain expert evidence and the applicability of Rule 53.03 and Rule 4.1.01.[6]

In Westerhof, the trial judge ruled inadmissible certain expert opinion evidence concerning history, diagnosis and prognosis from various health practitioners who were either treating practitioners or non-party experts. Non-party experts are experts who are not retained by parties to the litigation who form opinions based on observations or examinations relating to the subject matter of the litigation for purposes other than the litigation. The trial judge held that these witnesses were required to comply with Rule 53.03 and in the absence of compliance, their evidence was not admissible.

The trial did not go well for the plaintiff and the jury award was modest. The action was dismissed because the trial judge found that the plaintiff's claim for non-pecuniary general damages did not meet the threshold prescribed by s. 267.5(5) of the Insurance Act[7] and the amount of the award for past loss of income was less than the credit to be applied for collateral benefits received.

The plaintiff's appeal to the Divisional Court was unsuccessful.[8] The decision of the Divisional Court became the leading and binding authority on the issue pending the decision of the Court of Appeal. The crux of the decision of the Divisional Court was that the focus should be on “the type of evidence sought to be admitted” and “not in the role or involvement of the witness”.[9] The Divisional Court held that compliance with Rule 53.03 was required in all cases where the evidence in issue is opinion evidence. On the other hand, where the evidence was factual, compliance was not required.[10]

The plaintiff in Westerhof appealed further to the Court of Appeal arguing that Rule 53.03 applied only to litigation experts, namely expert witnesses “engaged by or on behalf of a party to provide [opinion] evidence in relation to a proceeding.”[11]

In McCallum, the trial judge permitted several treating medical practitioners to give opinion evidence concerning the plaintiff's future employment prospects and future care needs without compliance with Rule 53.03. The trial took place prior to the decision of the Divisional Court in Westerhof. The jury in McCallum awarded substantial damages to the plaintiff. On appeal to the Court of Appeal, the defendant conceded that treating physicians may give opinion evidence directly related to their treatment of a patient but argued that the trial judge erred by allowing medical practitioners who had not complied with Rule 53.03 to give opinion evidence that did not arise directly from their treatment of the patient.[12]

Decision of the Court of Appeal

The Court of Appeal allowed the appeal in Westerhof and dismissed the appeal in McCallum.

The Court of Appeal clearly rejected the Divisional Court's conclusion that the type of evidence – whether fact or opinion – is the key factor in determining the applicability of Rule 53.03. The Court outlined the underlying general principles as follows:

Instead, I conclude that a witness with special skill, knowledge, training, or experience who has not been engaged by or on behalf of a party to the litigation 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's 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.[13]

The Court reaffirmed its observation in Moore v Getahun[14] that “the 2010 amendments to rule 53.03 did not create new duties but rather codified and reinforced … basic common law principles.”[15] As such the Divisional Court erred in failing to consider and apply pre-2010 jurisprudence and, in particular, the decision of the Court of Appeal in Marchand v Public General Hospital Society of Chatham[16] which held that a treating physician called to testify about the facts of his or her own involvement or the opinions that went to the exercise of his or her judgment was a fact witness and not a “rule 53.03 witness.”[17]

The Court noted that while historically these witnesses have been described as “fact witnesses” because their evidence is derived from their observation or involvement in the underlying facts, there is confusion by describing such witnesses as fact witnesses. As such, Simmons J.A., writing for the Court, preferred to call them “participant experts”. The Court distinguished between three types of experts, namely: experts retained by a party, participant experts and non-party experts. The Court held that the wording of the 2010 amendments “supports the view that rule 53.03 does not apply to participant experts or non-party experts”.[18]

The Court noted that while the Osborne Report identified a number of problems related to litigation experts there was nothing in the report that indicated “an intention to address participant experts or non-party experts, whose evidence is relevant because of their observation of or participation in the events underlying the litigation.”[19]

Moreover, the Court of Appeal agreed with the submissions of the parties and interveners that the effect of the Divisional Court's ruling would “actually exacerbate the problems of expense and delay that it purports to alleviate.”[20] The Court further noted that “[r]equiring participant witnesses and non-party experts to comply with rule 53.03 can only add to the cost of litigation, create the possibility of delay because of potential difficulties in obtaining rule 53.03 compliant reports, and add unnecessarily to the workload of persons not expecting to have to write rule 53.03-compliant reports.”[21] Relieving these categories of experts from Rule 53.03 compliance avoids creating further concerns about access to justice.

Implications of Westerhof

This decision is of significant importance and gives considerable guidance as to the application of Rule 53.03 and the requirements to deliver a Form 53 from non-party experts and participant witnesses. While the issue frequently arises in personal injury actions, this decision will have widespread importance to all litigation matters. There has been considerable uncertainty in respect of the applicability of Rule 53.03 to opinion evidence from such witnesses as fire marshal investigators, accountants, business valuators and appraisers who may be called to give evidence based on opinions generated outside the context of a formal litigation retainer. Westerhof relieves some of this uncertainty for these types of experts as well. The Court of Appeal's decision is consistent with the long line of jurisprudence that predates the 2010 amendments. The Court of Appeal has eliminated some of the artificial barriers and unnecessary expense created by the wide interpretation of Rule 53.03 given by the Divisional Court and some trial judges. It must be remembered that the Court of Appeal's decision applies only to the procedural requirements of the Rules and does not in any way impact the substantive law applicable to the admission of expert opinion evidence.

As a note of caution, however, where a party seeks to adduce opinion evidence from a non-party expert or participant expert, the evidence must remain within the boundaries of the witness's observation of or participation in the events at issue. To the extent that the expert witness is to be asked questions that are outside of this boundary, (ie. strays into true opinion evidence) the evidence will not be admitted without Rule 53.03 compliance.

There remains some uncertainty as to how this boundary will be defined and no doubt trial judges will be required to make difficult evidentiary rulings based on the general principles outlined in Westerhof. However, this decision gives greater guidance to the development of the law in this area.

The article originally appeared in Professional Liability and Discipline Litigation, Volume XVI, No. 2, a journal devoted to issues of professional liability and discipline, published by Federated Press.

The author gratefully acknowledges the assistance of Alex R. Sharpe, student-at-law, Lerners LLP for assistance in the preparation of this paper.

[1] Coulter Osborne, Civil Justice Reform Project: Summary of Findings & Recommendations, (Toronto: Ministry of the Attorney General, 2007).

[2] Stephen Goudge, Inquiry into Pediatric Forensic Pathology in Ontario (Toronto: Ministry of the Attorney General, 2008).

[3] RRO 1990, Reg 194.

[4] Osborne, supra note 1 at 75-76.

[5] 2015 ONCA 206 [Westerhof].

[6] Ibid at paras 5-16.

[7] RSO 1990, c I.8.

[8] Westerhof v Gee Estate, 2013 ONSC 2093 (Div Ct).

[9] Ibid at para 21.

[10] Ibid at para 21.

[11] Westerhof, supra note 5 at para 12.

[12] Ibid at paras 16-17.

[13] Ibid at para 60.

[14] 2015 ONCA 55 (the Court of Appeal released separate reasons for this decision in late March despite hearing it with the Westerhof and McCallum appeals) [Moore].

[15] Westerhof, supra note 5 at para 73 citing Moore, supra note 14 at para 52.

[16] (2000), 51 OR (3d) 97 (CA) [Marchand].

[17] Westerhof, supra note 5 at paras 67-68 citing Marchand, supra note 16 at para 120.

[18] Westerhof, supra note 5 at para 80.

[19] Ibid at para 79.

[20] Ibid at para 86.

[21] Ibid at para 86.

Professional Liability and Discipline Litigation, Volume XVI, No. 2, Federated Press

Peter W. Kryworuk

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