Referrals to National Constitutional Courts: A Comparative Examination of Constitutional Judicial Referrals

Many judicial systems utilize referrals, a process in which one court has the ability to call upon another court, usually a superior court, for definitive interpretations of law. The referral process is most widely known from its use in the European Court of Justice, which has long thrived on receiving referrals on questions of European law (known as preliminary references) from national courts within the European Union. Despite the attention, the ECJ is far from the only court that utilizes the referral process. U.S. state and federal courts use certified questions and interlocutory appeals, and many national judicial systems in Europe utilize referrals for constitutional questions. The ECJ’s preliminary reference process is itself derived from the constitutional referral processes previously adopted in several national judiciaries of the EU member states. However, both theory and data at the national level remain sparse, with ECJ preliminary reference research dominating the literature. In this paper I examine the constitutional referral process at the national level, using data from three constitutional courts (Germany, Czech Republic, and Slovenia) over a 20-year time period. I also use interviews with judges to test different theories of why lower ordinary courts refer cases to their national constitutional courts. There currently remains a lack of theory and empirical data examining why lower ordinary courts choose to refer certain cases to their respective national or federal constitutional courts. The original dataset used in this paper is used to analyze the many factors that can influence the submission and acceptance of referrals to national constitutional courts, as well as the outcomes of those referral cases.