The use of expert opinion evidence is increasing in Canadian criminal trials, and along with it is a growing judicial disquiet regarding the impact of such evidence on the fact-finding function within the trial process. This paper, intended as an introduction to the subject matter, consists of two parts: the first part reviews the admissibility requirements for expert opinion evidence generally; the second part focuses on practical considerations for counsel arising from the revised two-part test for admissibility endorsed by the Supreme Court of Canada in White Burgess Langille Inman v Abbott and Haliburton Co, 2015 SCC 23, [2015] 2 SCR 182. The author also provides a comparative analysis to the treatment of expert evidence in the United States throughout the paper.

This paper is part of a collection presented at LESA’s Criminal Advocacy – Experts program held in Calgary on May 14, 2016 and in Edmonton on May 28, 2016.