What is the test for certifying a class action?

The starting point is recognition that the original certification order by Winkler J. contemplated a two-stage process in the class action. At the first stage, a common issues trial would determine questions of liability. At the second stage, with the agreement of all parties including the plaintiffs, “individual trials will be necessary for a final determination of the claims of each class member, in particular to determine issues of causation, reliance and damages arising from the claims”: see Carom v. Bre-X Minerals Ltd. (1999), 1999 CanLII 14794 (ON SCDC), 44 O.R. (3d) 173 (S.C.), at para. 88.