Allegiance in International Armed Conflicts: The Role of the Duty of Fidelity in International Humanitarian Law

The duty not to betray the social group is an ancient socio-political concept adopted by authorities to regulate the loyal behaviour of their members. Such duty has been legally regulated for centuries and now forms part of the domestic legal systems of contemporary states. Known in English as allegiance, the duty of fidelity is a fundamental concept of law that gains notoriety in times of armed conflicts. However, allegiance has been overlooked by scholars of international law as a factor in the design, interpretation and application of the rules of international humanitarian law (IHL) that protect individuals during armed conflicts and limit the capacity of states to choose methods of warfare. This study analyses the role that the concept of allegiance plays in the rules of IHL applicable in international armed conflicts. This is done by determining the contemporary meaning of allegiance in state practice, the ways it has been introduced into international law, and its use by relevant actors in six areas of IHL. The investigation reveals a rich historical practice around the concept of allegiance, its incorporation in rules and discussions of IHL, and the employment of this concept for multiple and diverse purposes: from the alleged basis for conferring protected status to civilians, to the alleged basis for denying protected status to combatants; from a protected element of occupied population, to a corruptible element of enemy population outside occupation; and as a presumption of dangerousness for enemy aliens, the required mens rea for desertion, and a vague term to determine connection between belligerent parties and armed groups. This study clarifies the contemporary understanding of allegiance, and confronts the concept with treaty provisions, case law, and academic debates relevant to the use of allegiance in IHL. Additionally, the study explores the relation between domestic law and international law applicable during international armed conflicts and the overlooked position of individuals of dubious loyalties such as traitors, collaborators, deserters, internal enemies, and corrupters.