ABSTRACT
At the heart of the controversy surrounding the McNaghten Rules has been a conflict between the legal and psychiatric professions. Although admitted as a fob to ward off the proponents advocating abolition of the death penalty, the diminished responsibility defence has done much more than spare undeserving murderers from a conviction of murder. The diminished responsibility defence has answered the prayers of those who call for individualisation within the rule of law and has stepped in to save mentally abnormal killers from a murder conviction where defences of automatism or insanity would have failed them. It has also saved mentally abnormal murderers from an inappropriate finding of insanity with consequent mandatory indefinite hospitalisation. The diminished responsibility defence’s major triumph has been its resolution of the medico-legal controversy underpinning the McNaghten Rules since the time of their enactment. The most trenchant critics of the insanity defence were the psychiatric profession who felt that the law embraced an outdated test of insanity.
