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Nov 8, 2018

Ont. C.A. clarifies role of “participant expert” witnesses in granting appeal and ordering new trial where Court satisfied that trial judge erred with respect to admission of “participant expert” evidence

Posted in Evidence | Experts

Author Bevin Shores

In Imeson v. Maryvale (Maryvale Adolescent and Family Services), 2018 ONCA 888, the Court of Appeal granted the appellant’s appeal and ordered a new trial, concluding that the trial judge erred with respect to her admission and treatment of “participant expert” evidence.

The underlying claim, which concerned allegations of sexual assault, had proceeded to a trial before a jury in which the jury had accepted, in material part, that the plaintiff had been assaulted by a person identified as “Tony Doe.” The appellant (defendant in the underlying action) appealed.

As is noted at paragraph 1 of the decision, the appeal “illustrates the importance of scrutinizing [participant expert] evidence to ensure that the participant expert does not exceed his or her proper role.”

Justice van Rensburg, writing for the Court, provided a concise overview of the context for and issues to be addressed in the appeal at paragraphs 3-8:

“[3]          The appellant’s central argument on appeal is that the trial judge erred in admitting the opinion evidence of Dr. Kerry Smith, a mental health clinician who treated the respondent and who gave evidence at trial as a participant expert. As a participant expert, he was exempt from the requirements that apply to litigation experts under r. 53.03 of the Rules of Civil Procedure, R.R.O. 1990, Reg. 194.

“[4]          The appellant says the trial judge’s error was compounded by her instruction to the jury to consider such evidence in determining whether the sexual assaults occurred.

“[5]          The appellant also takes issue with the trial judge’s decision to admit into evidence both Dr. Smith’s oral testimony and the summaries he had prepared based on handwritten notes, which contained details of his treatment sessions with Mr. Imeson, as well as various comments and opinions.

“[6]          For the reasons that follow, I would allow the appeal and would direct a new trial of the action concerning the alleged sexual assaults of the respondent by Tony “Doe”.

“[7]          As I will explain, Dr. Smith ought not to have been permitted to provide opinion evidence that went to the issues of whether the alleged sexual assaults occurred (liability) and whether Mr. Imeson suffered harm that was caused by such assaults (causation). The expert opinions that were elicited in this trial for such purposes went beyond Dr. Smith’s role as a participant expert under Westerhof  (Westerhof v. Gee Estate, 2015 ONCA 206, 124 O.R. (3d) 721, leave to appeal refused, [2015] S.C.C.A. No. 198). Under Westerhof, a participant expert’s exemption from r. 53.03 is lost to the extent the expert’s opinion is not based on the expert’s observation of or participation in the relevant events and not formed as part of the ordinary exercise of his or her skill, knowledge, training and experience while observing or participating in such events.

“[8]          Furthermore, Dr. Smith’s expert opinions going to the issues of liability and causation failed to satisfy the threshold requirements of admissibility under the first step of Mohan (R. v. Mohan, [1994] 2 S.C.R. 9), as that test has been clarified in White Burgess Langille Inman v. Abbott and Haliburton Co., 2015 SCC 23, [2015] 2 S.C.R. 182, and ought to have been excluded under the second step of the admissibility test because the prejudicial effect of such evidence outweighed its probative value.”

The underlying facts of both the circumstances in issue and the evidence at trial are set out in detail at paragraphs 9 through 52. Materially, the trial judge permitted the expert, Dr. Smith, “to testify about ‘his observations of, impressions formed regarding and treatment provided to the plaintiff as set out in the reports prepared by him’. She ruled that he was not to give opinion evidence as to any other matter, including: (1) whether Mr. Imeson would ever get out of prison; (2) whether he fit the characteristics of someone who had been sexually abused; and (3) whether he matched the characteristics that predatory sex offenders seek out. The exception was that Dr. Smith was permitted to give an opinion about the therapy he would have recommended had Mr. Imeson not terminated treatment. The trial judge cautioned counsel to exercise appropriate caution in their questioning of Dr. Smith to abide by her ruling.” (para 32) The trial judge also permitted Dr. Smith’s reports to be filed in their entirety.

The trial judge gave mid-trial instructions to the jury that “she had determined that Dr. Smith’s evidence was admissible to provide certain opinions, and that any statements Mr. Imeson made to Dr. Smith while taking a history or in the course of therapy were not to be taken as proof that the contents of the statements were true, but only that they were made” (para 38) and that “Dr. Smith cannot speak to causation per se. All he can speak to is his observations and assessments”(para 45). 

Acknowledging at paragraph 53 that “[a] trial judge’s decision with respect to the admissibility of expert evidence is entitled to deference and reversible on appeal only if there is an error in principle or a material misapprehension of the evidence, or if the decision is unreasonable,” the Court was nonetheless satisfied that the trial judge had committed such an error.

Justice van Rensburg provided a thorough analysis, examining the case law concerning participant experts and expanding upon the principles espoused in Westerhof as they pertained to the issues under consideration:

“[58]       As the trial judge recognized, great care was required to ensure that Dr. Smith did not provide any opinion evidence that exceeded the scope of proper opinions to be offered by a participant expert. Unfortunately, she permitted that to happen by admitting Dr. Smith’s unredacted reports into evidence and permitting him to testify about anything that was contained in the reports.

“[59]       In considering the proper scope of Dr. Smith’s evidence as a participant expert, it is important to remember how participant experts differ from litigation experts.

“[60]       In the civil litigation context, a litigation expert is subject to r. 53.03. This rule requires, among other things, an expert report that sets out the expert’s opinions, as well as an acknowledgment of the expert’s duty. Typically, an expert report provides a “roadmap of the anticipated testimony and specific limits may be placed on certain areas of testimony”: Bruff-Murphy (Litigation guardian of) v. Gunawardena, 2017 ONCA 502, 138 O.R. (3d) 584, at para. 62, leave to appeal refused, [2017] S.C.C.A. No. 343. The expert’s report will provide the framework for discussion about the proper scope of the expert’s testimony.

"[61]       In contrast, under Westerhof, participant experts may give opinion evidence without complying with r. 53.03. Typically, any opinions that are sought to be introduced are found in the clinician’s clinical notes and records, or in reports prepared for the purpose of consultation and treatment.

"[62]       In Westerhof, this court explained the proper role of a participant witness, at para. 60, as follows:

[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:

    “[63]       If participant experts proffer opinion evidence extending beyond these limits, they must comply with r. 53.03 “with respect to the portion of their opinions extending beyond those limits”: Westerhof, at para. 63. In acting as a gatekeeper, trial judges have the important task of ensuring that participant experts do not exceed their proper role or, if they do, that there is compliance with r. 53.03.

    “[69]       The trial judge’s attention was firmly on ensuring that Dr. Smith did not offer any opinions beyond what was contained in his reports (apart from the one discrete issue about treatment). She did not focus on the opinions that were in the reports, and consider whether any or all of the contents of the reports exceeded the scope of proper opinions to be offered by a participant expert.

    “[70]       I am prepared to accept that it was appropriate for Dr. Smith in his role as a participant expert to provide evidence about Mr. Imeson’s mental condition, the treatment that he provided, Mr. Imeson’s response to treatment, and the therapy he would have recommended had Mr. Imeson not terminated treatment. As the trial judge recognized, such evidence goes to the question of whether Mr. Imeson suffered harm. However, the fact that Dr. Smith might properly have given evidence on those matters would not make his unredacted reports admissible, and allow him to testify about everything that was contained in his reports.

    “[71]       In the circumstances of this case, it was particularly important to consider the nature of the various opinions proffered by Dr. Smith in his reports and the purpose for which they were being led before permitting Dr. Smith to testify as a participant expert witness. As I have noted, Dr. Smith completed his reports (except for the one dated February 17, 2015) approximately a year after Mr. Imeson had discontinued his therapy. According to Dr. Smith, he made thematic connections in the reports, which were not present in his handwritten notes. At the time, he knew that Mr. Imeson had commenced litigation. In these circumstances, it is difficult to imagine why Mr. Imeson would have requested that Dr. Smith prepare the reports other than for the purpose of litigation. In my view, these circumstances blurred Dr. Smith’s role.

    “[72]       Applying Westerhof in the circumstances of this case, Dr. Smith’s opinion evidence included evidence falling outside the proper scope of evidence tendered by a participant expert.

    “[73]       As Westerhof instructs, an opinion offered by a participant expert must be given as part of the ordinary exercise of the witness’s skill, knowledge, training and experience. Here, any opinion offered by Dr. Smith that sought to draw a causal link between the alleged sexual assaults and Mr. Imeson’s later behaviour could not have been based on his skill, knowledge, training and experience while he was involved in Mr. Imeson’s treatment. Rather, Dr. Smith testified that, in his therapeutic role, he accepted Mr. Imeson’s statements that he had been abused as true, and he confirmed that it was not his role to determine if the trauma happened, but only to trust what he was being told.

    “[74]       Westerhof also instructs that the opinion given by a participant expert must be based on the witness’s observation of or participation in the events at issue. Here, Dr. Smith testified as to the problems typical of survivors of childhood sexual abuse – evidence going to the issue of whether the assaults occurred. His evidence about survivors as a group was not based on his observation of, or treatment of, Mr. Imeson, and thus went beyond the proper scope of any opinion he could provide as a participant expert.

    “[75]       I conclude that, despite the trial judge’s recognition that the role of a participant expert is restricted, she permitted Dr. Smith to exceed his proper role by allowing him to testify about anything contained in his reports, and in admitting the reports into evidence, without first carefully examining what opinions were included in the reports, and the purpose for which it was proposed that the jury consider such opinions.”

    In light of the conclusion that the trial judge had erred with respect to Dr. Smith’s evidence, it was not, strictly speaking, necessary to consider the trial judge’s admissibility analysis under Mohan. However Justice van Rensburg observed at paragraph 76 that “given that I would send this matter back for a retrial, it may be helpful to discuss the appellant’s Mohan/White Burgess arguments as they relate to that evidence.”

    Justice van Rensburg began with a review of the law concerning admissibility of expert evidence under R. v. Mohan, [1994] 2 S.C.R. 9 and White Burgess Langille Inman v. Abbott and Haliburton Co., 2015 SCC 23, [2015] 2 S.C.R. 182:

    “[80]       There are two steps in assessing the admissibility of expert evidence under the Mohan/White Burgess framework: White Burgess, at paras. 23-24.

    “[81]       The first step in determining admissibility is for the court to assess whether the proposed expert evidence meets the threshold requirements that the evidence is (i) logically relevant; (ii) necessary to assist the trier of fact; (iii) not subject to any other exclusionary rule; and (iv) proffered by a properly qualified expert who is willing and able to provide evidence that is impartial, independent, and unbiased: see White Burgess, at paras. 23, 53; Mohan, pp. 20-25.

    “[82]       If the proponent of the evidence establishes the threshold for admissibility, the second discretionary gatekeeping step is for the trial judge to determine whether the potential benefits of admitting the evidence outweigh its potential risks to the trial process: White Burgess, at para. 24."

    Justice van Rensburg agreed “that Dr. Smith’s opinion evidence that was tendered on the issues of liability and causation did not meet the threshold criteria to be admissible as expert evidence, as the evidence was not necessary and Dr. Smith did not have the required expertise. As that decides the threshold question, I need not deal with other aspects of the threshold criteria.” (para 90)

    “[88]       In my view, it cannot be said that Dr. Smith’s evidence linking Mr. Imeson’s subsequent conduct to the alleged sexual abuse was essential to assist the jury since Dr. Smith was not even qualified to give such evidence. While he had the qualifications of a mental health clinician (the expertise that was accepted by the trial judge), his qualifications were not considered in connection with the opinions sought to be elicited from him. Dr. Smith was permitted to give opinion evidence related to the issue of whether the alleged abuse occurred, even though none of Dr. Smith’s qualifications demonstrated expertise in sexual abuse.

    “[89]       Dr. Smith estimated that between 25% and 30% of the inmates he saw had suffered from childhood sexual abuse. However, the fact that Dr. Smith understood that many of his patients had suffered from childhood sexual abuse does not, of course, make him an expert in the field. While Dr. Smith had expertise in treating prisoners with trauma, he did not have particular expertise in childhood sexual abuse. Accordingly, Dr. Smith was not qualified to offer an opinion about the problems typical of survivors of sexual abuse, or as to the relationship between the alleged sexual assaults and Mr. Imeson’s subsequent difficulties, including the commission of the first murder.”

    Justice van Rensburg also considered the second component of the admissibilty framework, namely whether the potential benefits of admitting the evidence outweighed the potential risks to the trial process, concluding “Dr. Smith’s opinion evidence going to the issues of liability and causation not only exceeded the scope of proper opinions to be offered by a participant expert, but also failed to satisfy the Mohan/White Burgess test for admissibility” (para 100).

    “[93]       In this case, the admission of Dr. Smith’s opinion evidence carried a number of risks to the trial process.

    “[94]       One such risk was that the jury might conclude that Dr. Smith’s testimony of what he was told by Mr. Imeson was proof of the truth of Mr. Imeson’s narrative. The trial judge addressed this risk with the hearsay caution.

    “[95]       The admission of Dr. Smith’s opinion evidence presented other risks to the trial process. 

    “[96]       First, there was the danger that Dr. Smith’s evidence would usurp the jury’s function of deciding credibility. As noted by the Supreme Court in R. v. Marquard, [1993] 4 S.C.R. 223, at para. 49, “credibility is a notoriously difficult problem, and the expert’s opinion may be all too readily accepted by a frustrated jury as a convenient basis upon which to resolve its difficulties”.

    “[97]       Second, the jury had before it, in Dr. Smith’s unedited and unredacted reports, a great deal of material that was irrelevant to issues in the proceedings, but that contained tremendous oath-helping potential. For example, Dr. Smith once referred to an incident where Mr. Imeson admitted to having taken another inmate’s medication. Mr. Imeson’s explanation, according to Dr. Smith’s report, was that he came forward with the information because “he had committed himself to honesty”.

    “[98]       To her credit, the trial judge acknowledged that the oath-helping concern was genuine, but determined that it could be addressed through her mid-trial jury instruction and in her final instructions. She did not, however, weigh all the risks I have identified against the possible benefits of admitting the evidence, or consider how the risks might be mitigated other than through the hearsay caution. In my view, the hearsay caution was insufficient to address the various risks present in this case, including the very real risk of oath-helping.

    “[99]       As this court noted in Llorenz, oath-helping evidence should not be admitted simply because it is led for another purpose. A court must still weigh the probative value of the evidence against its prejudicial effect: “In cases which turn on the question of which one of two witnesses is telling the truth, there is the danger that a jury may attach significant weight to the oath-helping aspect of the evidence of an expert, even if instructed to do otherwise”: Llorenz, at para. 32.”

    As to the effect of the trial judge’s error, Justice van Rensburg concluded that the error was indeed fatal and required a new trial:

    “[103]    The respondent’s success at trial was dependent on the jury’s having accepted that Mr. Imeson had been sexually abused by Tony “Doe” and that the abuse caused him harm. Dr. Smith’s evidence ought not to have been admitted on those issues; however, the jury was specifically instructed to consider his evidence together with all of the other evidence in determining whether the sexual assaults occurred. The only proper disposition, in my view, is to allow the appeal and to direct a new trial.”

    Imeson v Maryvale 2018ONCA0888

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