Indeterminacy and the Law of Restitution

So, is restitution indeterminate? Yes and no. Yes, there is an unavoidable element of indeterminacy in the effort to state rules of the law of restitution. That, however, is hardly a phenomenon unique to the law of restitution. If restitution is indeterminate, so are contract and tort. The fact that current Restatement makes such liberal use of phrases such as "to the extent necessary to avoid unjust enrichment" is merely a matter of drafting style, attributable in large measure to the fact that this field of law is still relatively little understood. Courts dealing with restitution claims should be no more willing to explain their decisions merely by vague references to unjust enrichment than they would feel about making similar assertions in cases involving other fields of law. There is more to the Restatement than section one's truism that "A person who has been unjustly enriched at the expense of another is required to make restitution to the other." There is, however, no use denying that in some areas it is difficult or impossible to state the rules of restitution in simple black and white terms.