How to Design a Constitutional Court? Evidence from the Netherlands

Courts crucially rely on public support to ensure compliance with rulings and safeguard their independence from political interference. Recent years have seen a surge in judicial reform proposals in many countries, often justified as necessary to enhance the legitimacy of courts in the public’s eyes. While much research has focused on the public's reaction to reforms that restrict judicial power (e.g., Aydin-Cakir, 2024; Engst and Gschwend, 2024), less attention has been paid to how institutional design features shape public support for courts. This study leverages the ongoing debate in the Netherlands about the introduction of a constitutional court to study the public's preferences for its institutional design. Unlike most democracies, Dutch courts are currently prohibited from reviewing the constitutionality of laws. However, calls for judicial reform have grown louder in recent years, and the current government has proposed establishing a constitutional court. The situation in the Netherlands provides a rare opportunity to explore public preferences for least three reasons. First, citizens' preferences are unshaped by an existing constitutional court structure. Second, the issue is high on the political agenda, which makes the issue much less abstract for citizens than hypothetical reforms. Finally, the debate about the design of a completely new court is much less driven by partisan considerations than specific, often court-curbing, reforms that serve a governing majority. This paper employs a preregistered conjoint experiment with a representative sample of Dutch citizens to examine preferences regarding key design elements: diversity among justices (gender, ethnicity, and regional representation), judicial appointment and tenure procedures, eligibility requirements for justices, and the scope of judicial authority. Moreover, the study explores how preferences for institutional design differ across relevant subgroups, and to what extent preferences are contingent on worries about political polarization and the rise of populism. The paper's findings shed light on what kind of reforms might increase the court's popular support and strengthen judicial institutions against growing populist and authoritarian challenges, with implications well beyond the Dutch case.