Judicial Review of the Improper Policy Implementation of Treaties

In recent years the courts of England and Wales have come to recognise a new iteration of judicial review which this article terms ‘review of improper policy implementation of treaties’ or ‘RIPIT’. RIPIT enables a reviewing court to scrutinise a domestic policy document which is promulgated for the purpose of securing compliance with a legislatively unincorporated treaty for its consistency with that treaty. This article discusses the emergence of RIPIT and defends it against an important objection which may be levelled against it: namely that, by engaging in RIPIT, courts are acting inconsistently with constitutional principles concerning the proper legal use of treaties in the United Kingdom's ‘dualist’ legal system. It argues that, properly understood, RIPIT entails the application of well‐established judicial review doctrine in a manner entirely consistent with established constitutional principle and case law. The emergence of RIPIT, however, does provide a valuable opportunity to reflect on the suitability of some common modes of expressing the relationship between treaties, UK law and the domestic courts, including the term ‘dualism’ itself.