How judges disagree about international law: European law and judicial dissents on the Supreme Court of Norway

How do supreme court judges disagree about international law? With the expansion of international law, national judiciaries play an important role in interpreting, applying, and implementing international – but also in resisting or challenging it. Existing research has chiefly explored the dynamic interactions between international law and national judiciaries in terms of whose agents national courts are: Are they resisting international law on behalf of national governments or do they rather serve as the extended arm of international courts? This model is reflected in e.g. literatures on how national courts use the EU’s preliminary reference procedure, how supreme courts cite international human rights law treaties and case law, or how courts non-democratic regimes use international law to legitimise authoritarian rule. Hence, national courts are assumed to engage in a delicate balancing act, weighing international legal authority against the sovereign discretion of the national government. However, this ’supranational authority versus national sovereignty’ dimension does not exhaust the possibilities: Judges disagree on many things, and often such disagreements are essentially political disagreements on ideologies, philosophical outlooks, or doctrinal perspectives, as evidenced by studies on judicial behaviour in diverse jurisdictions. These prevalent conflict dimensions are just as likely to manifest in cases that engage international law as they are in cases based purely in national law. National judiciaries are therefore unlikely to act as a unitary actor vis-a-vis international law, and disagreements about cases concerning international law are just as likely to reflect conflicts regarding other issues as principled stances on international law. Thus, when judges disagree on how to interpret and apply international law sources, their disagreement may reflect their overall disagreements on law and policy, rather than a simple sovereigntism–supranationalism dimension. In light of this, this paper seeks to provide a broader conception of how national courts engage with international law. Theoretically, we assume that international law will be used as a tool in a domestic judicial political game, and that political conflicts such as left–right, individualism–collectivism, libertarianism–authoritarianism, or centre–periphery, are just as likely to dominate these conflicts as the supranationalism–sovereigntism dimension. Employing data on judgments from the Supreme Court of Norway from 1990 to 2020, we examine how Supreme Court justices dissent in cases citing the European Convention of Human Rights and European Union law. The Supreme Court of Norway is an illustrative case because its increasing treatment of IL sources – chiefly, the ECHR and EU law – is associated with varying levels of dissent among judges. By doing this, the paper makes three contributions: First, we demonstrate that employing general theories of judicial politics and judicial decision-making can advance the analysis of how national courts use international law. Second, we demonstrate that by paying more attention to the conflict dimensions prevalent in the national political context, we gain a richer understanding of how courts use international law. Third, we show how assumptions about the primacy of the supranationalism–sovereigntism dimension might be premature.