Rationales: rejected, imagined and real – provocation, loss of control and extreme mental or emotional disturbance

What makes intentional killing under provocation less reprehensible than murder? The answer to this question determines the rationale for the law; and the choice of the primary rationale – justificatory or excusatory – determines the scope and fundamental features of the partial defence.In this article, I attempt to parse through two reforms – one promulgated by the Model Penal Code 1980 (MPC), the other by the Law Commission for England and Wales – and compare their versions of the defence both to each other and to the ‘loss of self-control’ defence of the Coroners and Justice Act 2009 in the hope of determining and appraising the governing rationales for each version of the defence. I conclude that the largely justificatory defence of provocation developed by the Law Commission (and to a lesser degree the ‘loss of self-control’ defence) is legally and morally preferable to the largely excusatory defence proposed by the MPC.