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Criminal Code Act 1983
159Trial for murder – partial defence of diminished responsibility
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159 Trial for murder – partial defence of diminished responsibility
(1) A person (the defendant) who would, apart from this section, be
guilty of murder must not be convicted of murder if:
(a) the defendant's mental capacity was substantially impaired at
the time of the conduct causing death; and
(b) the impairment arose wholly or partly from an underlying
condition; and
(c) the defendant should not, given the extent of the impairment,
be convicted of murder.
(2) Expert and other evidence may be admissible to enable or assist
the tribunal of fact to determine the extent of the defendant's
impairment at the time of the conduct causing death.
Criminal Code Act 1983 138
(3) If the defendant's impairment is attributable in part to an underlying
condition and in part to self-induced intoxication, then, for deciding
whether a defence of diminished responsibility has been
established, the impairment must be ignored so far as it was
attributable to self-induced intoxication.
(4) The burden of establishing a defence of diminished responsibility is
a legal burden and lies on the defence.
(5) A defendant who would, apart from this section, be liable to be
convicted of murder must be convicted of manslaughter instead.
mental capacity, of a defendant, means the defendant's capacity
to:
(a) understand events; or
(b) judge whether his or her actions are right or wrong; or
(c) exercise self-control.
underlying condition means a pre-existing mental or physiological
condition other than of a transitory kind.