Unjust enrichment: what we owe to each other

In some quarters, the focus of unjust enrichment scholarship has shifted from loss and gain towards the defendant’s ‘involvement in the story’—what she has done to warrant liability. The goal of this shift is to fit unjust enrichment within the ‘doer-sufferer’ template of ‘corrective justice’ theories of private law. I argue that this shift fails to reconcile unjust enrichment with the commitment to equal freedom upon which these theories depend. But we can justify restitution without forsaking the Kantian concern with rational agency. In this article, I endorse a contractualist approach to mistaken payments: a particular use of the state’s coercive power is just if it is one that everyone could rationally choose; everyone could rationally choose a rule placing the burden of risk for mistake with payees, if that rule does not make any such payee worse off than she was prior to the impugned transaction.