The ICJ’s contribution to the law on jurisdictional immunities is elucidated by Professor Roger O’Keefe. He argues that, through its case law in this area, the ICJ has affirmed basic aspects of the international law of jurisdictional immunities, clarified a few more specific points, and variously crystallised, consolidated, and catalyzed the further development of important customary rules on controversial issues in relation to civil and criminal proceedings respectively. Through its work in this field, the Court has reasserted an orthodox, possibly conservative vision of the role of jurisdictional immunities in the international legal order.

This chapter considers the ICJ’s relationship with other courts and tribunals through the dual prism of integration and fragmentation. The author argues that three factors influence the degree of the Court’s integration or fragmentation: the identity of the court, the substance of the law, and the procedures employed. The author selects three legal issues that have been considered by the ICJ and other courts and tribunals in recent years: jurisdiction over issues of immunity involving treaties that do not expressly refer to immunity; inferring specific intent for genocide; and the nature of consular assistance as a treaty obligation, individual right or human right. These issues provide insight into the way that identity, area of law and procedure influence integration or fragmentation among international courts.

States have taken different approaches to incorporating relevant jurisdictional immunities into their domestic legal systems. Some common law countries have adopted foreign state immunity acts that codify jurisdictional immunities as a matter of domestic law. Other civil law countries, such as Italy, apply rules of foreign state immunity based on customary international law more directly. At the same time, domestic courts have adjudicated disputes related to jurisdictional immunities by interpreting and applying their domestic laws against the backdrop of international law and the customary international law norms that govern the contours of foreign state and foreign official immunity. Assessing challenges brought before international tribunals to immunity determinations made by domestic courts in Europe is helpful, and specifically a challenge brought by individual claimants before the European Court of Human Rights to the United Kingdom’s determination that Saudi Arabia was entitled to jurisdictional immunity from civil claims for torture, and a challenge brought by Germany before the International Court of Justice to Italy’s determination that Germany did not enjoy jurisdictional immunity from civil claims for World War II–era crimes. Domestic courts in Canada and Italy subsequently considered these decisions in reaching their own conclusions about the scope of foreign state immunity under their domestic statutes. This examination shows that immunity cases defy categorization along a European/ North American divide.

In this concluding chapter I first summarize the key findings across the three case studies, and offer an overall conclusion to the research question posed in the introduction. I also discuss some hypotheses, generated from the case study findings, which may explain the variations between cases and the variations between different types of accountability mechanisms. Finally, I sketch out some aspects of a reform agenda.