The Court of Justice and treaty revision: A case of strategic leniency?

Students of European Union judicial politics have debated the credibility of legislative override as constraint on the behaviour of the European Court of Justice. Yet because of the high political hurdles for the passage of treaty amendments, treaty revision has been dismissed as the ‘nuclear option’, exceedingly effective but difficult to use. However, when treaties are being renegotiated, the ability of member state governments to pass treaty amendments to either punish or reward the Court is greater. We argue that this may induce the Court of Justice to display more leniency towards member states in cases coinciding with ongoing treaty negotiations. To test this hypothesis, we examine the outcome of all infringement cases adjudicated between 1961 and 2016. We find that the European Court of Justice is significantly less likely to render adverse rulings in cases concomitant with the final, most salient stage of treaty negotiations. Our analysis suggests that the relationship between treaty revision and judicial behaviour may be more nuanced than commonly assumed in the literature