Resisting the European Court of Justice, the European Union’s supreme court, Poland has sparked resurgent judicial nationalism across the political bloc.

The situation centers on the Polish Supreme Court’s Oct. 7 ruling that Polish law is generally supreme over EU law. That ruling represents a fundamental rebuke to the EU’s political character — its aspiration to ultimate legal authority. The 2009 Treaty of Lisbon declares that “the Treaties and the law adopted by the [EU] on the basis of the Treaties have primacy over the law of Member States.”