Part 3
Matters of justification or excuse

Insanity

23 Insanity

(1) Every one shall be presumed to be sane at the time of doing or omitting any act until the contrary is proved.

(2) No person shall be convicted of an offence by reason of an act done or omitted by him when labouring under natural imbecility or disease of the mind to such an extent as to render him incapable—
(a) of understanding the nature and quality of the act or omission; or

(b) of knowing that the act or omission was morally wrong, having regard to the commonly accepted standards of right and wrong.

(3) Insanity before or after the time when he did or omitted the act, and insane delusions, though only partial, may be evidence that the offender was, at the time when he did or omitted the act, in such a condition of mind as to render him irresponsible for the act or omission.

(4) The fact that by virtue of this section any person has not been or is not liable to be convicted of an offence shall not affect the question whether any other person who is alleged to be a party to that offence is guilty of that offence.