The terms “unjust enrichment,” “restitution,” “quasi-contract” and “constructive trust” cause the average lawyer to recoil with apprehension (although she doesn’t show it, of course). We were forced to grapple with some of these ancient legal concepts in law school, but we quickly migrated to more modern legal principles, and although we may have remembered the terms (any lawyer worth his salt can throw around the terms unjust enrichment and restitution), the depth of knowledge of most lawyers on these topics is shallow at best. We were relieved when we could move on to things like the Uniform Commercial Code, which dates back only to the early 1950’s.
In fact, it’s easy to trace “unjust enrichment” and related terms back as far as the 1600s, and earlier. A search on Google Book Search reveals a volume titled “Unjust Enrichment in England before 1600.” References to Roman Law are also not difficult to find.… Read the full article