RESTITUTION AND UNJUST ENRICHMENT

In a general and broad sense, ‘restitution’ means restoration, i.e. returning something lost or stolen. From a legal point of view, ‘restitution’ refers to a specific set of remedies designed to restore what the defendant has gained at the plaintiff 's expense to the plaintiff. By their very nature, restitutionary remedies always entail something wrong that therefore has to be redressed.

Restitution is applicable to a wide range of different situations, from contracts made by mistake to uses of another's assets without the owner's consent. In all such cases, the legal system tries to restore things to the scenario of nothing wrong having even happened by returning everything to the right place, as it was before the wrongful conduct that triggered restitution. In doing so, all possible restitutionary solutions share a common goal: preventing unjust enrichment.

What we currently know as the law of restitution and unjust enrichment was developed from a number of more specific remedies and causes of action that have been identified by common law and civil law systems in different ways. Quasi-contracts, constructive trusts, accounting for profits, rescission, equitable lien, subrogation, indemnity and contribution, among others, are legal responses in situations in which someone does not rightfully gain the right to hold another's assets or to get profit from them.

Legal systems have tried to identify a general principle on which these separate remedies are based, and they have found it in the general prohibition on unjust, or unjustified, enrichment. In fact, it is generally acknowledged that no one is entitled to retain unjustified enrichment. In all legal systems the law on unjust enrichment is largely devoted to distinguishing between unjust and not unjust enrichment. Transfers of money or assets made in performance of valid contracts or as a valid gift are deemed justified, while transfers made by mistake or as a consequence of void contracts or invalid gift s are not justified. The former allow the money to remain; the latter require restoration, as noted above.