The chapter considers the ICJ’s contribution to the law of State responsibility, looking back to the Court’s contribution to the codification of that law by the ILC: looking at the Court’s current attitude to the ILC’s Articles on State Responsibility; and looking to the future, addressing one of the main challenges facing the Court in this field, that of multilateral disputes. The author concludes that the Court has been an important player in this field of international law, and it has made a significant contribution to vesting the ILC Articles with the authority they have today. According to this chapter, the Court has an important role to play going forwards in the growth and development of community interest litigation for the enforcement of erga omnes obligations.

The analysis in this chapter proceeds from the assumption that shared responsibility for a breach of a shared obligation has been established and focuses on the content of that responsibility. In the case that secondary obligations of reparation or cessation arise, what can be claimed from which responsible actor, and to what extent is this influenced by the fact that the underlying primary obligation is shared? And if injured parties wish to effectuate these secondary obligations through international adjudication, are there any obstacles to the claiming of cessation and reparation? It will ultimately be argued that conceiving of the content of shared responsibility as consisting of shared obligations incumbent on all responsible actors can help untangle which of the responsible states or international organizations is bound to do what in terms of cessation and reparation. In this context, the distinction between divisible and indivisible shared obligations has an important role to play. After all, determining whether responsible actors are each bound only to their own share of cessation or reparation or whether, alternatively, all of them become bound to achieve a common result has direct implications for what can be claimed from whom.