The Effect of War on Law — What Happens to Their Treaties When States Go to War?

Abstract

War is the ultimate game-changer. It leads to a rupture in the relations between states. This includes, potentially, a disruption of their legal relations as established in treaties (and may even affect those with third states). Many wars have radically realigned the underlying bases of treaties to the extent that their original rationale can no longer be sustained, resulting in their modification or even termination. History also provides examples, as recent as the conflicts of the twentieth century, of states going to war precisely to shrug off the yolk of onerous treaties. Yet, abrogation as an outcome has not always been the automatic consequence of the outbreak of war. Some treaties have continued to apply during the armed conflict, owing to their purpose as, for example, in the case of treaties aimed precisely at regulating the conduct of belligerents, such as the Geneva Conventions of 1949, or guaranteeing the rights of neutrals in the case of war.

Contemporary international law recognises an intermediate position, whereby treaties between parties to an armed conflict might be automatically suspended for the duration of the conflict, only to be revived afterwards, even if in a modified form, to reflect the new post-conflict modus vivendi.

In the post-war period, the question of the effect of armed conflict on treaties was first considered, albeit tangentially, during the process of the elaboration of the law of treaties. However, the states participating in the 1968-69 Vienna Conference declined to deal comprehensively with the issue, preferring instead to reserve, in a saving clause in what became article 75 of the VCLT, the legal position so as not to `prejudge any question that may arise in regard to a treaty from...the outbreak of hostilities between States'. In 2004, the ILC turned its attention to the topic. A first reading of a set of draft articles on the effects of armed conflicts on treaties was completed in 2008 on the basis of the proposals of the first Special Rapporteur, Sir Ian Brownlie, following an extensive analysis of applicable state practice and doctrine. The final set of draft articles was adopted, on second reading, in 2011 (2011 articles) under the guidance of the second Special Rapporteur, the Swiss jurist Lucius Caflisch.

Keywords: treaties, armed conflict, international law commission, United Nations