The German Federal Constitutional Court broke with the European Court of Justice by disregarding a judgement. In an interview with ZDF, Policy Fellow Thu Nguyen remarks on the historical background of this conflict.
The dispute is ongoing—who has higher judicial authority between the two courts? This conflict is not new, in fact according to Nguyen "this is a conflict that has existed since the beginning of the European legal order."
You can find the full article (in German) here.