How Does International Law Work: What Empirical Research Shows

Abstract

This paper for the Oxford Handbook of Empirical Legal Studies (forthcoming 2010) assesses what empirical research shows in response to three questions concerning international law: (i) why international law is produced and invoked; (ii) how international law is produced; and (iii) how and under what conditions international law matters. We assess variation in response to these questions across different areas of international law, since different actors and institutions are present, and distinct processes and mechanisms are used in such areas as international human rights, criminal, trade, investment, and regulatory law. For each of these questions, we contend that understanding state behavior requires “unpacking” the state and exploring variation at the national and subnational level. We find that most empirical work indicates that international law’s impact varies in light of such factors as the situation of the state in question (including its regime type and level of wealth); the congruity of the issue with domestic political contests; and the role of intermediaries such as government elites or civil society in conveying international law norms into domestic systems.