Jus Post Bellum and Proportionality in International Law (Launch of Two Books)

On April 30, The Hague Institute for Global Justice hosted a joint launch of two books covering critical questions ofjus post bellum (the law and morality of the transition from armed conflict to peace), jus ad bellum (the law and morality of resort to force) within jus in bello (the doctrines applicable for using force in the midst of conflicts).

Jus Post Bellum: Mapping the Normative Foundations

The first book, edited by Professor Carsten Stahn,Jennifer S. Easterday, and Jens Iverson, provides a detailed understanding of the development and nature of jus post bellum as a concept, including its foundations, criticisms, and relationship to related concepts (such as transitional justice, and the responsibility to protect).

It investigates the relationship of the concept to jus ad bellum and jus in bello, and its relevance in internal armed conflicts and peacebuilding. There are significant problems brought about in relation to the ending of conflict, including indicators for the end of conflict, exit strategies, and institutional responses, which are also assessed.

The book identifies the key components of a ‘jus’, or body of law, drawing on disparate bodies and sources of international law such as peace agreements, treaty law, self-determination, norms governing peace operations and the status of foreign armed forces, environmental law, human rights, and amnesty law. The temporal and theoretical boundaries and content of the concept are explored and clarified.

Taking into account perspectives from multiple disciplines, the book is important reading for scholars, practitioners, and students across many fields, including peace and conflict studies, international relations, and international humanitarian law. | Read more

Proportionality in International Law

Written by Professor Michael A. Newton andProfessor Larry May, the second book critically assesses the law of proportionality in a uniquely interdisciplinary way to provide normative philosophical and legal analysis that addresses some of the most pressing debates in the field today such as human shields, drone warfare, cyberwar, and counterinsurgency.

The principle of proportionality defines the permissible boundaries for the initiation and conduct of modern wars. The case studies discussed in this book are predominantly from the perspective of those who make decisions in the midst of armed conflict, bringing analytic rigor to the debates as well as sensitivity to facts on the ground.

This book contrasts the applications of proportionality in both jus ad bellum (the law and morality of resort to force) and within jus in bello (the doctrines applicable for using force in the midst of conflicts). The authors analyze modern usages of proportionality across a wide range of contexts enabling a more complete comprehension of the values that it preserves.

Proportionality in International Law provides the reader with a unique interdisciplinary approach, offering practitioners and policymakers alike greater clarity over how proportionality should be understood in theory and in practice. | Read more


  • Professor Naomi Roht Arriaza
    Distinguished Professor of Law, Hastings College of the Law
    University of California
  • Judge Howard Morrison
    Judge, International Criminal Court and International Criminal Tribunal for the Former Yugoslavia

Editors Professor Carsten Stahn, Jennifer S. Easterday, and Jens Iverson from Leiden University and Professor Michael A. Newton from Vanderbilt University Law School also presented during this event

Further Reading

Active: Distinguished Speaker Series

The Distinguished Speaker Series (DSS) showcases eminent practitioners in international affairs and is the centerpiece of the Institute’s high-level engagement with practitioners and academics in the city…