R v M'Naghten (1843)
Facts.
Daniel M’Naghten, suffering delusions of persecution, shot dead the Prime Minister’s secretary, mistaking him for the PM.
Issue.
When does insanity excuse a criminal act?
Held.
He was acquitted by reason of insanity. The judges laid down the M’Naghten Rules: an accused is excused only if, by reason of a defect of reason from disease of the mind, he did not know the nature of his act, or that it was wrong. India adopted this in s.84 IPC / s.22 BNS.
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