The Discoverability of Mistakes of Law

Abstract

The “mistake of law” category of unjust enrichment might be a more obscure cause of action were it not for s.32(1)(c) of the Limitation Act 1980. That provision postpones the limitation period in cases of “mistake.” Recent landmark judgments have interpreted s.32(1)(c) to extend time for bringing actions in mistake of law until there has been an authoritative judicial pronouncement on the point of law in issue. This understanding of discoverability is arbitrary, jurisprudentially strained, and internally inconsistent. It gives rise to serious problems in doctrine and policy. The courts should revisit their jurisprudence and consider the more coherent understandings of the discoverability principle that others have previously advanced.

Keywords: private law, restitution, mistake of law, Limitation Act, limitation postponement, reasonable diligence, abuse of process, settled view of law, Franked Investment Income Group Litigation, Prudential Assurance, Ipswich Town Football Club v Suffolk Constabulary, AB v Ministry of Defence