Imeson v. Maryvale (also known as
Maryvale Adolescent and Family Services) et al.
[Indexed as: Imeson v. Maryvale]
2018 ONCA 888
Court of Appeal for Ontario, G.J. Epstein, van Rensburg and D.M. Brown JJ.A.
November 7, 2018
Civil procedure — Evidence — Expert evidence — Plaintiff suing for
damages for sexual assault — Mental health clinician who treated plaintiff
giving evidence at trial as participant expert — Trial judge limiting
witness’ testimony but admitting all of his non-contemporaneous
summaries of his session notes — Trial judge erring in effectively allowing
witness to provide expert opinion evidence that went to issues of whether
alleged sexual assaults occurred and whether plaintiff suffered harm
that was caused by such assaults — Opinions on liability and causation
going beyond witness’ role as participant expert — Witness’ opinions
going to liability and causation also failing to satisfy Mohan test for
admissibility of expert evidence.
The plaintiff brought an action for damages for sexual assaults allegedly
committed in the mid-1990s. As a result of three convictions in 2008 for second
degree murder, he was serving life sentences. He was treated in jail by S, a mental
health clinician. The trial judge permitted S to give evidence at trial as a participant
expert. She limited S’s testimony, ruling that he would be allowed to testify about
his “observations of, impressions formed regarding and treatment provided to the
plaintiff as set out in the reports prepared by him”. Those “reports” were summaries
prepared by S based on handwritten notes which contained details of his treatment
sessions with the plaintiff, as well as various comments and opinions. They were
prepared after the action was commenced. The trial judge admitted the reports
into evidence in their entirety and allowed S to testify about anything contained in
them. The action was allowed as against the defendant M. M appealed.
Held, the appeal should be allowed.
The trial judge ought not to have allowed S to provide expert opinion evidence
that went to the issues of whether the alleged sexual assaults occurred (liability)
and whether the plaintiff suffered harm that was caused by such assaults (causation).
The expert opinions that were elicited for such purposes went beyond S’s role as
a participant expert. A participant expert’s exemption from the requirements that
apply to litigation experts under rule 53.03 of the Rules of Civil Procedure, R.R.O.
1990, Reg. 194 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 these events. The trial judge recognized the limited
role of a participant expert. However, after ruling that S would be able 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 permitted him to
testify about anything that was contained in the reports, without exception. She
failed to consider whether any of the contents of the reports exceeded the scope of
proper opinions to be offered by a participant expert. The appeal should be allowed
on that basis. S’s opinions going to liability and causation also failed to satisfy the
Mohan test for the admissibility of expert evidence. Those opinions were not
necessary to the central liability question — whether the sexual assaults occurred.