Insanity

As an author of medico-legal reports, I read with interest the article by Reference Haque and CummingHaque & Cumming (2003) on intoxication and legal defences. I would like to comment in particular on their section under the heading of Insanity on p. 148.

First, the infamous M'Naghten rules are stated to have had their inception in 1943. I suspect this is a typographical error. The judges at the House of Lords gave their opinion on what the wording of the insanity defence should be a century earlier, in 1843. This followed on from M'Naghten's case that same year.

Second, the interpretation of the ‘knowledge’ requirements of ‘nature’, ‘quality’ and ‘wrong’ are stated to be restricted to a lack of legal rather than moral knowledge. I submit that this is not quite right. R v Windle [1952] at the Court of Appeal did indeed hold that the word ‘wrong’ means legally wrong, not morally wrong. However, R v Codere(1916) also at the Court of Appeal determined that the ‘nature’ and ‘quality’ of the act means its physical nature and quality. So, for the one limb it is a lack of legal knowledge, but for the other limb it is a lack of physical knowledge. Thus, there is a distinction in the interpretation of the knowledge requirements of the two limbs.

Third, psychopathy is given as an example of a condition that is capable of forming the insanity defence in its own right. Is this correct? Are the authors saying that psychopaths are legally insane? Is there a mistake here, or have I misunderstood?