Mobilising Judicial Voices: How and Why National Courts Express Their Opinions in the Preliminary Reference Procedure – A Case Study of Czechia

Abstract This article interrogates the national courts' pre‐emptive opinions expressed in the Article 267 of the Treaty on the Functioning of the European Union preliminary reference procedure from both theoretical and analytical angles. First, we theorise about the variety of factors influencing national courts' decision to supply the Court of Justice of the European Union with their views on EU law issues, categorising them into four groups: legalist , strategic , personal and institutional . In that way, we construct a sound theoretical framework for a more systemic study of the mobilisation of judicial voices in the process of European integration. Subsequently, we conduct a case study of Czechia. Utilising a new dataset of all preliminary references submitted by Czech courts (2004–2024, n = 131), we demonstrate that Czech judges openly articulate their positions more frequently than some of their colleagues from older member states. Dissimilar to existing research, our evidence also indicates that Czech supreme court judges frequently express their opinions explicitly, more so than lower level court judges, and that at some instances, such praxis is steady in time.