This chapter builds upon three streams of experience by its author: (a) one related to his six-year term as the first UN Special Rapporteur on human rights and counterterrorism (2005-2011), namely the identification of the absence of a proper international definition of terrorism as an important source of human rights abuses, (b) his observation of actual court practice and media coverage where definitional-conceptual elements of terrorism, in particular as to its aims, appear to be ignored despite being one of the cornerstones on which those legal definitions were built, and (c) his academic work pointing out that the instrumentalization of the human person, in breach of Immanuel Kant’s categorical imperative, comes through as a characteristic both of acts of terrorism and of human rights violations committed by States in the name of countering terrorism.

On the basis of reflecting on these experiences, and departing from his own best practice definition built on Security Council Resolution 1566 (2004) and included in his last report to the UN Human Rights Council, the author now proposes the removal of any subjective aim element from international definitions of terrorism, and its replacement with the objective element of the act amounting to the instrumentalization of human beings, typically victims of terrorism.

This introductory chapter by the editor discusses the goals of the book, introduces the questions central to it as well as develops a methodological framework. It relates to existing scholarship on the impact of human rights law upon other branches of international law and on the fragmentation of international law. It outlines the methodology that was applied in working towards this volume by presenting a range of distinctions that provide conceptual tools for detecting and assessing the different ways how international non-human-rights courts may refer to human rights. These include categories of human rights, sources of human rights norms, and three contexts for their application, namely due process rights applied in the proceedings of the court in question, substantive human rights norms as applicable law or basis for subject-matter jurisdiction, and interpretive reliance on human rights through systemic integration. The chapter also relates to the legitimacy of international courts by showing that how international courts relate to human rights norms matters for factors of legitimacy.

In the concluding chapter, the editor engages in a comparative and theory-building exercise across the jurisdictions covered in the book. There are important differences between international non-human-rights courts as to the legal basis for their application of human rights norms. While due process rights of the parties appearing before it, and systemic integration, are available for all courts, there are marked differences in issues such as standing by individuals, the status of human rights norms as applicable substantive law or basis for jurisdiction, and the patterns concerning which categories of human rights have made their way into other international courts. There are also clear examples of ‘other’ courts widening the scope of justiciable human rights, for instance through applying economic, social and cultural rights, or the right to property, or collective rights of peoples beyond the practice of actual human rights courts. In their application of human rights norms, 'other' international courts have at least so far tended to do so reflecting more the trend of humanisation, rather than constitutionalisation, of international law.