Treaty Exit and Intra-Branch Conflict at the Interface of International and Domestic Law

This chapter, forthcoming in the Oxford Handbook of Comparative Foreign Relations Law, considers two important and unresolved issues raised by unilateral withdrawal from or denunciation of treaties. The first issue concerns whether treaty obligations end in both international and domestic law after a state leaves a treaty. Exit often produces the same effects in both legal systems, but some withdrawals bifurcate a treaty’s status, ending its obligations in domestic law but continuing to bind the state internationally, or vice versa. The second issue concerns denunciations initiated by different branches of government. The decision to withdraw from a treaty is usually carried out by the executive acting unilaterally. Less well known, but potentially more fraught from a foreign relations perspective, are instances in which the impetus for exit originates with legislators or judges. Conflicts involving both dimensions of treaty exit stem from a common source – the different domestic and international rules governing how states enter into and leave treaties and the divergent policies that underlie those rules. The chapter develops a typology to categorize these conflicts, drawing upon examples of actual and potential treaty denunciations in several countries as well as actions by the executive, legislature, and judiciary that make such withdrawals more likel