The making of landmark rulings in the European Union: the case of national judicial independence

We study the conditions under which the European Court of Justice (ECJ) expanded the European Union's reach into issues of national judicial independence. The ECJ's 2018 ruling in a case known as Portuguese Judges contained a far-reaching constitutional interpretation that had a transformative impact on the European Union's rule of law crisis. We conduct a theoretically guided investigation into both the domestic origins and the judicial outcome in the Portuguese Judges case. We show how the ECJ, with implicit support from the majority of the Member States, strategically exploited suitable characteristics of an inconspicuous case to produce a landmark ruling that enabled unprecedented enforcement action against democratic backsliding in Poland and Hungary.