M'Naghten Rules (1843)

The insanity-defence standard from (1843) 8 Eng Rep 718, formulated by the House of Lords in response to the acquittal of Daniel M'Naghten: the accused is not responsible if, by reason of disease of the mind, they did not know the nature and quality of the act, or did not know it was wrong. The governing standard in England and Wales, applied in India under BNS § 22 / IPC § 84, and the baseline from which US law developed.