Incidental Determinations by International Courts and Tribunals: Subject-Matter Jurisdiction and Applicable Law in Proceedings Under Compromissory Clauses

Abstract

Many States are parties to treaties containing compromissory clauses. By virtue of such clauses, States consent to proceedings being commenced against them in relation to “disputes concerning the interpretation or application” of a particular treaty. In practice, disputes are brought before international courts and tribunals pursuant to such clauses that not only involve issues under the rules set out in the relevant treaty, but which also involve issues under rules found outside of the treaty (“external issues” and “external rules”). Can courts and tribunals that have been granted jurisdiction over “disputes concerning the interpretation or application” of a specific treaty decide such external issues? At present, it is not clear. This thesis proposes an answer to the above question. It will be argued that courts and tribunals named in compromissory clauses have subject-matter jurisdiction over claims concerning the interpretation or application of the relevant treaty, regardless of whether those claims involve issues under external rules. Moreover, by applying rules forming part of the applicable law, courts and tribunals can determine those external issues that they need to determine in order for them to be able to rule on claims within their jurisdiction. They can make what will be referred to as “incidental determinations”. They can do this because courts and tribunals exercising jurisdiction under compromissory clauses have an implied power to make such incidental determinations.