Professional negligence cases require expert evidence as to standard of care

Krawchuk v. Scherbak, 2011 ONCA 352 deals with the issue of professional negligence claims and proof.  It is a good source for the general principle that, except in extraordinary cases, expert evidence is required to establish the standard of care:

[123]     In my view, the difficulties associated with the trial judge’s analysis of Ms. Krawchuk’s claims against the real estate respondents started with the issue of the standard of care.  His analysis of this issue is, with respect, faulty, for two reasons.  First, the trial judge erred by holding that he could determine the standard of care without expert assistance: against this backdrop he refused to admit the only expert evidence tendered on this issue. Then, he erred by not identifying the standard of care.  See Fullowka v. Pinkerton’s of Canada Ltd., [2010] 1 S.C.R. 132, at para. 80.

[124]     As will be seen, the error of primary importance for the purpose of my analysis is the trial judge’s ruling that he could assess the various claims without having the benefit of expert evidence.  I start with some general observations.

[125]     To avoid liability in negligence, a real estate agent must exercise the standard of care that would be expected of a reasonable and prudent agent in the same circumstances.  This general standard, a question of law, will not vary between cases and there is no need for it to be established through the use of expert evidence. see Wong v. 407527 Ontario Ltd.(1999), 179 D.L.R. (4^th) 38 (Ont. S.C.), at para. 23, Fellowes, McNeil v. Kansa General International Insurance Co. (2000), 138 O.A.C. 28 (C.A), at para. 11. The translation of that standard into a particular set of obligations owed by a defendant in a given case, however, is a question of fact (Wong at para. 23, Fellowes at para. 11). External indicators of reasonable conduct, such as custom, industry practice, and statutory or regulatory standard, may inform the standard.  Where a debate arises as to how a reasonable agent would have conducted himself or herself, recourse should generally be made to expert evidence. 

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 [129]     In my opinion, in the particular circumstances of this case, the trial judge erred in concluding that he could identify the applicable standard of care without the benefit of expert evidence. This error was compounded by his failure to identify the standard of care that he thought was applicable and by his failure to address the import of the Code in relation to the question of the governing standard of care.

[130]     The jurisprudence indicates that, in general, it is inappropriate for a trial court to determine the standard of care in a professional negligence case in the absence of expert evidence.  See: Zink v. Adrian (2005), 37 B.C.L.R. (4^th) 389 (C.A.), at para. 43, Southin J.A., concurring; Gavreau v. Paci, [1996] O.J. No. 2396 (C.A.), at para. 1; Precision Remodeling Ltd. v. Soskin, Soskin & Potasky LLP, 2008 CanLII 31411 (Ont. S.C.), at para. 57; Dinevski v. Snowdon, 2010 ONSC 2715, at paras. 68-69; Adeshina v. Litiwiniuk & Co. (2010), 24 Alta. L.R. (5^th) 67 (Q.B.), at paras. 160-175.

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 [132]      While the authorities discussed above indicate that, as a general rule, it will not be possible to determine professional negligence in a given situation without the benefit of expert evidence, they do indicate two exceptions to this general rule.

[133]     The first exception applies to cases in which it is possible to reliably determine the standard of care without the assistance of expert evidence. As explained by Southin J.A. at para. 44 of Zink, this will be the case only where the court is faced with “nontechnical matters or those of which an ordinary person may be expected to have knowledge.”

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 [135]     The second exception applies to cases in which the impugned actions of the defendant are so egregious that it is obvious that his or her conduct has fallen short of the standard of care, even without knowing precisely the parameters of that standard: see Cosway v. Boorman’s Investment Co., 2008 BCSC 1482, at para. 35. As can be seen, this second exception involves circumstances where negligence can be determined without first identifying the parameters of the standard of care rather than identifying a standard of care without the assistance of expert evidence.