The Incongruity of the Rome Statute Insanity Defence and International Crime

Thus far, the insanity defence in international criminal law has slid quietly under the radar. It was all but ignored during the Rome Conference negotiations: while all other defences in Article 31 underwent various alterations, the mental incapacity defence was left virtually untouched. The definition of the defence adopted by Article 31(1)(a) of the Rome Statute borrows heavily from domestic formulations, in both its volitional and cognitive components. Underlying this transplantation of domestic tests into international law was an assumption that they would fit and function in the international context in the same way as in the domestic context. This article challenges that assumption. It is argued that both the volitional and cognitive components of the Rome Statute insanity defence are incongruous with international crime, on account of the fact that the contexts in which violations of international and domestic criminal law take place are materially different.