Are Advocates General Political? An Empirical Analysis of the Voting Behavior of the Advocates General at the European Court of Justice

The question whether political preferences of EU Member States play a role in the decision-making of the members of the European Court of Justice (ECJ) has so far gone largely unanswered in the literature. This paper formally tests the hypothesis that the political preferences of Member State governments are reflected in the decisions of the Advocates General, who are judge-like members of the ECJ. The empirical analysis is motivated by a novel model of the interaction between the Advocate General and the judicial panel. Based on this model, the paper develops a formal test to answer whether there is a relationship between the policy preferences of EU Member State governments with regard to European integration and the decision behavior of Advocates General appointed by these governments. It then tests this hypothesis using a newly assembled dataset combining information on agreements and disagreements between the opinions issued by the Advocates General and the ensuing judgments of the ECJ in preliminary ruling proceedings with information on political preferences of Member State governments obtained from party manifesto data. The results of this test suggest that the votes of Advocates General reflect the political preferences of the appointing governments vis-à-vis European integration.