Independence and impartiality through the lens of incompatible activities, disqualification and challenge: the ICJ, ITLOS, and inter-State arbitration

The members of the international courts and tribunals are expected to be independent and impartial. Their constituent instruments normally contain rules which aim at ensuring the independence and impartiality of judges and arbitrators. Such rules typically include provisions addressing activities incompatible with the judicial office, bars to the participation of a judge or an arbitrator in a particular case, when doubts about his/her impartiality arise. They sometimes address but are oftentimes silent on withdrawal, recusal or challenge. This article explores what types of activities can be said to be incompatible with the exercise of judicial functions or to bar the participation of a judge or an arbitrator in a particular case so as to shape the contours of the notions of impartiality and independence. It examines the existing normative arrangements and the practice of inter-State courts and tribunals, including the procedures and practice on withdrawal, recusal, challenge and the standard applied or applicable in assessing whether the requirements for independence and impartiality of international adjudicators have been met.