International Humanitarian Law Overview

Principles

Definition

International humanitarian law is a distinct body of public international law governing the conduct of armed conflict (jus in bello) and the academic field dedicated to its systematic study and analysis. As a research concept, it investigates the legal principles and rules designed to protect persons not participating or no longer participating in hostilities and to restrict the means and methods of warfare. Key characteristics include the principles of distinction between combatants and civilians, proportionality in attacks, and the prohibition of torture and inhuman treatment, underscoring its significance in mitigating human suffering, ensuring accountability for violations, and regulating state and non-state actor conduct during armed conflict.

Ontological type

Principles and Rules

Sources and Norms

Implementation and Enforcement

Key developments

Key Figures

Customary Norm Consolidation era

Thomas M. Franck [1] was a leading figure in the Customary Norm Consolidation era (1984-2002), with appointments at Washington University in St. Louis [3] and Princeton University [4]. In his 1997 paper Why Do Nations Obey International Law? [7], Franck advanced theories of compliance and legitimacy that helped explain how treaty-derived norms crystallize into customary obligations, guiding state practice and policy during this era. Harold Hongju Koh [2] was a central figure in the same era, with affiliations at the University of California, Berkeley [5] and Yale University [6]. Koh's analysis in Why Do Nations Obey International Law? [7] offered a doctrinal frame for assessing how legitimacy and compliance translate into customary norms, shaping debates on civilian protection, occupation law, and the development of relevant policy and doctrine in this era.

Global Accountability Institutions era

Jack L. Goldsmith [1] is a leading scholar in the Global Accountability Institutions era, with affiliations at the University of Chicago [3] and University College London [4]. His analysis in The Limits of International Law [7] critiques the limits of international legal mechanisms to deter mass atrocities and attribute state responsibility, a contribution that clarified why normative diffusion alone was insufficient for accountability in this era. Eric A. Posner [2] is a prominent thinker linked to Washington University in St. Louis [5] and the University of California, Berkeley [6] during this period. His co-authored work The Limits of International Law [7] helped shape debates on deterrence, state responsibility, and the role of international tribunals in accountability, influencing norms and policy in humanitarian prohibitions.

Sovereignty-Centered Accountability era

Jennifer M. Welsh[1] is a central figure in the Sovereignty-Centered Accountability era (2017–2023), with scholarly activity anchored at McGill University[2] and Vrije Universiteit Amsterdam[3]. Her key contributions in this era, as reflected in the 2019 paper Close cousins in protection: the evolution of two norms[4], center on tracing how two protection norms have evolved and on clarifying their implications for accountability within sovereign-friendly protection regimes, which helped identify normative and practical levers for legitimacy and enforcement in state-centered humanitarian governance.