Acquiescence and Its Role in the Settlement of Island Disputes: “Silence May also Speak”, But to What Extent?

Acquiescence usually takes the form of silence or absence of protest in circumstances that reasonably call for objections. This notion has been frequently invoked by States in territorial cases, especially recent island disputes. Based on the latest international jurisprudence, this article will study whether, and to what extent, the special case of island disputes would affect international courts’ consideration of acquiescence. As suggested by this study, international jurisprudence has set a high threshold for proof regarding the elements of acquiescence. Nevertheless, acquiescence seldom constitutes a sole and independent legal title for the settlements of island disputes, but as an important element for the establishment of a historic title, treaty interpretation and the application of effectivités. In addition, it is of more frequent occurrence that international courts contemplate the possibility of transferring a title to an island based on the notion of acquiescence, but the conditions for the transfer of title are strictly defined.