Primacy and the remedy of disapplication

This article explores the EU principle of primacy and, in particular, the requirement that incompatible national rules be disapplied by the domestic courts. Objections to disapplication generally involve concerns about legal certainty as regards existing decisions or relationships – leading to an extensive case law (e.g.) on the non-publication of Union acts or rules of res judicata. More recently, the ECJ has faced concerns about how the prospective disapplication of national rules might create a legal vacuum capable of endangering legitimate public interests (pending adoption of fully compliant measures by the Member State). The available case law suggests the emergence of a new body of principles that qualify the full implications of primacy. But the precise division of labour between the Court and the domestic judges remains unclear. And the conditions governing the exercise of each jurisdiction might offer insufficient legal protection against the full risks of a damaging legal vacuum.