Unjust Enrichment, Restitution, and “Moral Obligation”
Chapter 8 explained how promissory estoppel can sometimes be used to ameliorate the harsh consequences of consideration doctrine by enforcing a promise that induced justifiable reliance. Although the remedy of restitution is available in a variety of different situations, both within the bounds of contract law and beyond them, in one of its aspects it serves a purpose similar to promissory estoppel by allowing for the enforcement of obligations that do not qualify as contractual. Having drawn this general parallel, it must be stressed that restitution and promissory estoppel have very different conceptual bases. Restitution is not predicated on accountability for promise. In fact, its usefulness is greatest when no promise has been made. Its purpose is the restoration of an unfair gain. Its focus is on cases in which one party has obtained a benefit at the expense of another under circumstances that make it unfair for the recipient to retain the benefit without paying for it.