“The essence of unjust enrichment is that “something must have been given by the plaintiff and received and retained by the defendant without juristic reason.” Kerr v. Baranow, 2011 SCC 10, at para. 32. Canadian law permits recovery whenever the plaintiff can establish three elements: (1) an enrichment of or benefit to the defendant; (2) a corresponding deprivation of the plaintiff; and (3) the absence of a juristic reason for the enrichment. Kerr at 33; Pettkus v. Becker, 1980 CanLII 22 (SCC), [1980] 2 S.C.R. 834, at p. 844; Peel (Regional Municipality) v. Canada, 1992 CanLII 21 (SCC), [1992] 3 S.C.R. 762, at p. 784, [1992] S.C.J. No. 101, at para. 32.
Unjust enrichment is not fault-based. It is “animated by the belief that, regardless of any wrongdoing, unwarranted transfers ought to be reversed.” Mitchell McInnes, The Canadian Law of Unjust Enrichment and Restitution, 2nd Ed. (Toronto: LexisNexis, 2022), at §1.01[2][a][i]. I will cite this text simply as “McInnes”.
Liability for unjust enrichment is strict. “Restitution is triggered, regardless of any wrongdoing, by an unwarranted transfer between the parties.” McInnes, at §1.01[2]. Despite this, parties usually find it irresistible as an element of advocacy to inject an emotional element – wrongdoing – into the analysis, but again, wrongdoing is not required.”