Although the Igbo customary law of succession, which espouses the primogeniture principle, has recently been lambasted by the Nigerian courts for violating the equality provisions of the Nigerian Constitution and discriminating against women, the judicial engagement with the Igbo inheritance law...

This article will assess whether the changes in asylum-seeker movement over the most recent ten years to more significantly involve new states, such as the conflicts in Syria and Ukraine, may be bringing about changes in how we assess customary international law on refugee law. The recent...

In the most recent few years, customary international law is increasingly crystalizing to affirm that states must grant nationality to children born in their territory, if they would be otherwise stateless. In prior scholarship, this author has argued that such a norm of a customary...

After the Supreme Court of Canada’s decision in Nevsun Resources Ltd. v. Araya, Canadian courts can, in theory, apply customary international law (CIL) to private corporate actors for the purposes of a transnational tort claim pursuant to allegations related to human rights and/or...

Despite the large number of environmental agreements at the global, regional and bilateral levels, the role of customary international law remains of great importance in practice. First, many treaties which are in force remain largely unimplemented. Secondly, treaties only bind those States that...

This article examines whether or not the FET standard has become a rule of customary international law. The article contains the first empirical analysis of this question based on the two conditions under which a treaty-based norm can transform into a customary rule. The article will argue that...

Before 1804, France was strictly divided in terms of legal regimes: a part was under Roman civil law while the majority of the territory was under customary laws which, as with common law, gave more flexibility to judges and fewer rights to the state. This dichotomy offers the unique opportunity...

In recent years, the banking industry has witnessed several cases of excessive risk-taking that frequently have been attributed to problematic professional norms. We conduct experiments with employees from several banks in which we manipulate the saliency of their professional identity and...

In recent years, the banking industry has witnessed several cases of excessive risk-taking that frequently have been attributed to problematic professional norms. We conduct experiments with employees from several banks in which we manipulate the saliency of their professional identity and...

Rules of customary international law provide basic legal protections to foreign investors doing business abroad. These rules remain of fundamental importance today despite the growing number of investment treaties containing substantive investment protection. In this book, Patrick Dumberry...

It is often observed in the literature on customary international law that the identification practice of the International Court of Justice for customary norms deviates from the traditional definition of customary law in Art. 38 (1) lit. b of the ICJ Statute. However, while there are many...

Indigenous customary laws often conflict with or contradict contract laws of foreign legal systems. If an indigenous person wishes to conduct an international transaction according to their customs, problems may arise where customs are inconsistent with governing laws. This paper examines the...

The paper examines the potential of customary international law to protect global public goods. In particular, it focuses on the question whether customary law can contribute to the mitigation of climate change. The analysis proceeds in the three steps. First, it will have a closer look at the...

This article articulates an explanatory theory of customary international law under which precedential concerns are central to explaining CIL formation, compliance and change. In contrast with previous theories, which emphasize the role of reciprocity, retaliation and reputation in sustaining...

The question of the existence of legal protection for foreign investors under customary international law (or “custom”) has always been controversial. As a result of this perceived lack of established customary principles, States concluded thousands of bilateral investment treaties in the...

This paper examines the formation and evolution of customary international law in the field of foreign investment (Parts II and III) and its various forms interaction with international treaties, focussing mainly on BITs (Parts IV to IX). Although a comprehensive study on the customary rules for...

This contribution to a symposium on Kiobel v. Royal Dutch Petroleum Co. examines two ways of looking at the question of corporate liability under customary international law. It argues that the Second Circuit was wrong to ask whether a “norm of corporate liability” exists in the abstract and...

Customary international law is one of the three main sources of international law; lamentably, it has historically received little attention from law and economics scholars, despite providing rich material for economic analysis. In this chapter, we provide a concise overview of recent research...

This contribution analyzes the role of consent in the formation of customary law. It will challenge the assumption that customary norms cannot bind states against their will. Relying on game theory, it will distinguish between different situations and argue that the role of consent differs...

Customary law has been criticized from very different angles. Rational choice theorists claim that what looks like custom is nothing but self-interest. Positivists doubt that anything beyond consent assumes the force of law. In this paper, we adopt an experimental approach to test these claims....

Customary law has been criticized from very different angles. Rational choice theorists claim that what looks like custom is nothing but self-interest. Positivists doubt that anything beyond consent assumes the force of law. In this paper, we adopt an experimental approach to test these claims....

Customs and usages in England : achieving interpretive accuracy by giving effect to unexpressed intent / Geoff R. Hall -- Usages and implied terms under French and Belgian positive law : a subjective approach tending toward objectivity / Lydie Van Muylem -- White space, implied terms, and the...

In their majority, public international lawyers postulate that for a new rule of customary law to originate, two conditions must be fulfilled: there must be consistent practice, and it must be shown that this practice is motivated by the belief that such behaviour is required in law. Maurice...

In their majority, public international lawyers postulate that for a new rule of customary law to originate, two conditions must be fulfilled: there must be consistent practice, and it must be shown that this practice is motivated by the belief that such behaviour is required in law. Maurice...

In their majority, public international lawyers postulate that for a new rule of customary law to originate, two conditions must be fulfilled: there must be consistent practice, and it must be shown that this practice is motivated by the belief that such behaviour is required in law. Maurice...

This book analyses the topic of protecting traditional cultural expressions (TCEs) in Latin America. It questions classic legal approaches and involves the interface of anthropology and law. The study analyses regional, national and local particularities of law on paper and law in reality. It...

Rational choice approaches to customary international law have gained in prominence in recent years. Although becoming increasingly sophisticated, they are not able to explain all phenomena of customary international law. This contribution claims that there are two different types of unwritten...

Rational choice approaches to customary international law have gained in prominence in recent years. Although becoming increasingly sophisticated, they are not able to explain all phenomena of customary international law. This contribution claims that there are two different types of unwritten...

This article considers the role of customary international law (CIL) in a world in which the treaty has become the predominant instrument of international legal cooperation. Far from rendering CIL irrelevant, the article argues that the increased use of more formal, institutionalized legal...

In four independent Chapters, I examine how norms guide our behavior in an uncertain world. Methodologically, I apply the toolbox of experimental economics to research questions that are on the interface between economics and law (especially Chapter 1 and Chapter 2), sociology (especially...