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A Tough Pill to Swallow 161
argued for a new construal of “total insanity.” 55 Erskine noted that true total
insanity, where one does not understand who he is, where he is, or what he is
doing, does not exist; rather, insanity may be “delusion where there is no frenzy or
raving madness…”. 56 Thus, the ground work was laid for the insanity defence to
be considered in cases where the accused is merely deluded, notwithstanding his
capability of some level of reasoning and forethought. This change represents a
marked departure from the traditional characterization of the insane as “idiots” 57
or “wild beasts”, 58 insofar as otherwise relatively intelligent people could be
considered insane in the right circumstances.
D. The M’Naghten Rules
The M’Naghten rules originated from M’Naghten’s Case, 59 and continue to
form a large basis for the modern conception of the NCR defence. M’Naghten
had fatally shot the English Prime Minister’s private secretary, believing him to be
the Prime Minister himself. His motivation in doing so was his delusional belief
that the government was persecuting him. M’Naghten was clearly able to make
out his insanity plea but his acquittal sparked public outcry which resulted in a
formal judicial “clarification” of the law on the insanity defence. 60 Thus, the
M’Naghten rule was declared as follows, that, in order to acquit a person on
grounds of insanity,“[i]t must be clearly proven that, at the time of the committing
of the act, the party accused was labouring under such a defect of reason, from
disease of the mind, as not to know the nature and quality of the act he was
doing, or, if he did know it, that he did not know what he was doing was
wrong.” 61
While this characterization of the defence was simple, it presented a severe
problem which persisted until rather recently in Canadian jurisprudence 62 , which
I will discuss below. The benefit of the M’Naghten rules is that they set out a
uniform guide by which to solicit expert evidence in determining the sanity of the
accused at the time of the alleged offence. It was no longer a question of the
accused’s general mental competence, sanity, or predilections. The expert would
simply be asked whether or not he thought the accused was deprived of his
understanding of right and wrong or his understanding of the nature and
consequences of his acts, with respect to the offence. 63 In England, the following
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Quen, supra note 48.
Ibid.
Berger, supra note 46.
Arnold’s Case, supra note 52.
Daniel M’Naghten’s case (1843), 10 Cl & F 200 at 210, 8 ER 718.
Quen, supra note 48.
Supra note 59 at 722 [cited to ER].
R v Chaulk [1990] 3 SCR 1303.
FA Whitlock, Criminal Responsibility and Mental Illness, (Toronto: Butterworths & Co, 1963) at 9.