Nuremberg established many important principles, notably with respect to the definition of crimes against humanity as part of customary law or of general principles of law, to the unavailability of certain defences, such as superior orders and official capacity or position, and to notions of criminal participation, such as the principle of command responsibility. However, the international tribunals at Nuremberg and Tokyo, and the successor trials held by various national military tribunals in the aftermath of the Second World War, left little in the way of guidelines applicable to sentencing issues in cases of war crimes and crimes against humanity. The tribunals occasionally appended a perfunctory final paragraph to their judgments reviewing ‘mitigating factors’, in the rare cases where these were deemed to be present. When the new generation of international criminal tribunals began to consider the issue of sentencing convicted persons, there was little precedent of any assistance.

In the course of their work, the ad hoc tribunals have now built up a substantial body of authority on the question of sentencing, even if the whole area remains somewhat nebulous, and precise guidelines from the Appeals Chambers remain to be established. In 2001, the ICTY Appeals Chamber said that whether the sentencing practice of the Tribunal ‘is far enough advanced to disclose a pattern is not clear’. The process has been described as ‘essentially discretionary’, although ‘[s]entences of like individuals in like cases should be comparable’.