Westerhoff And McCallum: More From The OCA On Expert Evidence

The Ontario Court of Appeal released its decision last week in Westerhof v. Gee Estate and McCallum v. Baker (2015 ONCA 206), which are the companion cases to Moore v. Getahun.  All three appeals were heard together.

The legal issue before the Court in Westerhof   and McCallum was whether participant experts and non-party experts could give opinion evidence without having to comply with Rule 53.03, which describes the deadlines and content requirements for expert reports.

The Court of Appeal held that the Divisional Court erred in concluding that the type of evidence – whether fact or opinion – is the key factor in determining to whom Rule 53.03 applies.

Rather, the Court of Appeal was unanimous in that participant experts and non-party experts may give opinion evidence without complying with Rule 53.03.  As a result, Rule 53.03 does not apply to the opinion evidence of a non-party expert or participant expert where he or she has formed a relevant opinion