What is the test for a claim against a defendant in a personal injury case?

A plaintiff must prove that: the defendant has been enriched; the plaintiff has suffered a corresponding deprivation; and the benefit and corresponding detriment occurred without a juristic reason. The court takes a straightforward economic approach to the first two elements – enrichment and corresponding deprivation. Other considerations, such as moral or policy questions, are dealt with at the juristic reason stage of the analysis. See Kerr v. Baranow, 2011 SCC 10, at paras. 32-41.