Striking the Balance between Custom and Justice - Creative Legal Reasoning by International Criminal Courts

Certain customary norms complicate the work of international criminal courts and tribunals (ICTS). The principle of legality prescribes that no one can be convicted for 'new' or ill-defined crimes, and the rules on personal immunity bar ICTS from prosecuting high-level defendants. In cases involving these issues, ICTS face the dilemma of weighing fundamental 'rule of law' principles against their core objective: to hold leaders accountable for international crimes. Various ICTS have resorted to what some commentators euphemistically call 'creative' application of customary international law but critics label as 'poor legal reasoning'. By examining examples of such rulings, with particular focus on a recent string of decisions by the International Criminal Court (ICC) regarding head of state immunity, this article attempts to identify and assess a modus operandi of ICTS confronted with the arduous choice between 'safe-bet' application of the relevant sources of law and ensuring international criminal justice.