A Systematic Approach to 'Unjust' and 'Unjustified' Enrichment

The law of enrichment addresses situations of misplacing wealth. It is not clear in English law whether the restitutionary claim in enrichment requires an ‘unjust’ or an ‘unjustified’ transfer of wealth. The author argues that the two adjectives indicate the existence of two claims, which differ in their structures and aims. ‘Unjust’ and ‘unjustified’ misplacements account for two different legal principles. ‘Unjust’ enrichments refer to a concept of fairness in legal transfers which is independent of strictly legal rules. ‘Unjustified’ enrichments trigger a legal response based on the lack of justification of the transfer. The two actions originate in Roman law. After having presented the origin and function of the claims, the first part of the article outlines their evolution in the German, French, and Italian legal systems. The second part examines whether the Roman law partition can be used to develop a systematic account for English law. Although the framework is still unsettled, it seems that the English law of enrichment may benefit from analysis in the light of a dual structure akin to the one which, in the author's view, characterizes the civil jurisdictions under examination.