Abstract

In a 2004 decision, the Supreme Court of Canada restated the law of unjust enrichment as it exists in the common law provinces of Canada. Unjust enrichment is said to arise where there is 'no juristic reason' for the defendant's enrichment and the plaintiff's corresponding deprivation. This appears to mark a movement away from the traditional common law approach, which answers the question whether an enrichment is unjust by reference to primary facts such as mistake, compulsion or undue influence. The new Canadian approach appears to bear some similarity to civilian legal systems, which may frame the inquiry according to whether the enrichment was supported by some legal justification, such as a contractual or other obligation. Through a comparative approach, the author shows that no legal system is actually thoroughly committed to an analysis of this kind; when deciding whether an enrichment is unjust, all systems look sometimes to the primary facts, and sometimes to justification through legal constructs like contracts. The author shows that if the new Canadian approach is to be made workable, it will require further elaboration in a number of directions.