Where General International Law meets International Humanitarian Law: Attribution of Conduct and the Classification of Armed Conflicts

Case law of the International Court of Justice and international criminal tribunals reveals different judicial attitudes toward the relationship among State responsibility law, international humanitarian law (IHL) and the classification of armed conflicts. The legal precedents on this topic have been called 'the most cited example of the "fragmentation of international law"'. This contribution examines this conflict, or fragmentation, in order to shed light on the question whether IHL, or its interpretation and application, has had any influence on the general international law of State responsibility. With arguments specifically derived from the nature of international humanitarian law and from the structural design of State responsibility law, the article demonstrates that international armed conflicts involve two States that are responsible for the acts of their forces through which they act. Having in mind this symbiotic relationship between IHL and State responsibility for purposes of the classification of conflict, the case law on this matter, which is often cited as an example of fragmentation, can to some extent be reconciled, as long as one recognizes that attribution rules have a certain influence on the scope and application of primary rules of IHL. The article concludes that IHL (and the interpretation thereof by international tribunals with subject-matter expertise) has exercised no influence on attribution rules as found in the general international law of State responsibility, apart from the recognition that primary rules of international law (such as IHL) may contain secondary leges speciales rules dealing with the attribution of conduct in times of armed conflict.