Expert Evidence in Class Actions Litigation: A Proposed Framework for a Reliability Analysis

Reliable expert evidence is critical to the adjudicative process. The Ontario Civil Justice Reform Project chaired by The Honourable Mr. Coulter Osborne, and the Inquiry into Pediatric Forensic Pathology in Ontario led by Commissioner Goudge1 each underscore the important role that expert evidence plays in judicial decision making. Reliable expert evidence is critical in class actions litigation where evidence concerning epidemiological, toxicological, and statistical evidence is often adduced to prove claims for hundreds, and in some instances, thousands, of class members. In such cases, Canadian courts are regularly faced with complex expert evidence relating to aggregated claims. Accordingly, sound decision making in class action litigation depends upon evidentiary reliability.