This article responds to five pieces published in the previous issue of the Leiden Journal of International Law, extolling the virtues of a new legal realism. I first express some doubts as to whether an awful lot can and should be expected from yet another new approach to the study of international law; earlier approaches widely heralded have quietly disappeared from sight, sometimes without leaving much trace. Subsequently, I discuss the extent to which the new international legal realism conceptualizes its notion of empirical reality, followed by a discussion on which interests the new insights spawned by new legal realism are to serve.

This rejoinder responds to criticisms by Jan Klabbers and Ino Augsberg of ‘The New Legal Realist Approach to International Law’ (Leiden Journal of International Law, Volume 28:2, 2015). The New Legal Realism brings together empirical and pragmatic perspectives in order to build theory regarding how law obtains meaning, is practised, and changes over time. In contrast with conceptualists, such as Augsberg, legal realists do not accept the priority of concepts over facts, but rather stress the interaction of concepts with experience in shaping law's meaning and practice. Klabbers, as a legal positivist, questions the value of the turn to empirical work and asks whether it is a fad. This rejoinder contends that the New Legal Realism has deep jurisprudential roots in Europe and the United States, constituting a third stream of jurisprudence involving the development of sociolegal theory, in complement with, but not opposed to, analytic and normative theory.

In this article, I suggest that one of the central characteristics of New Legal Realism is the productive tension between empiricist and pragmatist theories of knowledge which lies at its core. On one side, new realist work in its empiricist posture seeks to use empirical knowledge of the world as the basis on which to design, interpret, apply, and criticize the law. On the other, in its pragmatist moments, it explicitly draws attention to the social and political contingency of any claims to empirical knowledge of the world, including its own. As a consequence, it is distinctive of much scholarship in the New Legal Realist vein that it continually enacts creative syntheses of different philosophies of truth in an attempt to be, in Shaffer's words, ‘positivist . . . interpretivist, and legal realist all at once’. The first part of this article draws on existing historical accounts of legal realism briefly to trace the problematic and ambiguous place of scientism in the legal realist tradition. Then, in the second and more important part of the article, I argue that the ambivalence of the legal realists’ vision has left us, in certain contexts, with a complicated form of mixed legal-scientific governance which has proved remarkably and surprisingly resilient in the face of late twentieth century critiques of scientific objectivity. This may be one of the most enduring legacies of the ‘old’ legal realists for those today who work in the New Legal Realist vein.

This article argues that human rights law – which mediates between claims about universal human nature, on the one hand, and hard-fought political battles, on the other – is in particular need of a richer exchange between jurisprudential approaches and social science theory and methods. Using the example of the Inter-American Human Rights System, the article calls for more human rights scholarship with a new realist sensibility. It demonstrates in what ways legal and social science scholarship on human rights law both stand to improve through sustained, thoughtful exchange.

The New Legal Realist approach to international law builds from a jurisprudential tradition that asks how actors use and apply law in order to understand how law obtains meaning, is practised, and changes over time. The article addresses the jurisprudential roots of the New Legal Realism, its core attributes, and six important components in the current transnational context. In the pragmatist tradition, the New Legal Realism is both empirical and problem-centred, attending to both context and legal normativity. What is new is the rise of transnational activity that gives rise to an enlarged scope of transnational problem-solving through international law in radically new ways across areas of law, and the growth of empirical study of these phenomena. The article concludes by addressing the potential risks of the New Legal Realist approach in terms of scientism and relativism, and it responds to them.