Multiple Attribution of Conduct

This paper investigates whether rules on attribution of conduct under the Articles on State Responsibility (ASR) and the Articles on the Responsibility of International Organization (ARIO) can be purposefully used to assess and adjudicate issues of shared responsibility. Obviously, co-authorship of an internationally wrongful act (or multiple attribution) is only one of the many potential situations of shared responsibility in international law. Both the ASR and the ARIO clearly recognize the possibility that one wrongful act may determine the responsibility of a plurality of international subjects at the same time. They also contain a clear recognition that states may act jointly, and so may international organizations, or states and international organizations. The paper argues that, despite the many difficulties in reconciling the ASR and ARIO framework with concepts of shared responsibility, in principle there is no logical or legal reason why a given conduct cannot be attributable to one or more states and/or one or more international organizations at the same time. Indeed, multiple attribution is the default position whenever more two or more subjects of international law act together.