The Function of Proportionality in Maritime Delimitation and Its Limits: Some Reflections on the Jurisprudence of International Courts and Tribunals

In accordance with the jurisprudence of international courts and tribunals,the role of proportionality in maritime delimitation can be summarized as two aspects: first,it constitutes one of the‘relevant circumstances' necessary to adjust the provisional delimitation line; second,it plays a certain role in the‘proportionality test'stage as a verification of equity. Therefore,given its long coastal lines,the proportionality should play a significant role in China's settlement of the disputes over maritime boundaries with its neighbors. However,in the case law of international adjudication,there are no criteria which can be utilized to determine the exact degree of the ‘difference of coastal lengths' calling for adjustment of provisional delimitation lines,or the ‘significant disproportion'in the final proportionality test. In contrast,the international judicial bodies themselves enjoy great discretion. Therefore,with an aim to overcome the problem of subjectivity,international adjudication in the future may introduce more quantitative criteria so as to improve the legal certainty in the field of maritime delimitation.