lc290 Partial Defences to Murder report - Law Commission

5.55 Conversely, others objected to a test that would involve the jury judging whether
the offence should be reduced from murder to manslaughter because it is “very
imprecise and subjective” 60 and gives the jury “a unstructured discretion”. 61
5.56 We share those objections. To direct a jury that mental abnormality reduces
murder to manslaughter if sufficiently serious that it ought to do so, leaves the
jury to set its own standard for deciding what ought to reduce murder to
manslaughter.
The Scottish Law Commission
5.57 In June of this year the Scottish Law Commission presented its Report on
Insanity and Diminished Responsibility. 62 Until the Full Bench decision of the
Court of Session in Galbraith v. Lord Advocate (No 2) 63 the law on diminished
responsibility in Scotland was set out in the direction to the jury of Lord Alness in
HM Advocate v. Savage 64 as follows:
It is very difficult to put it in a phrase, but it has been put in this way:
that there must be aberration or weakness of mind; that there must
be some form of mental unsoundness; that there must be a state of
mind which is bordering on though not amounting to insanity; that
there must be a mind so affected that responsibility is diminished
from full responsibility to partial responsibility-- in other words, the
prisoner in question must be only partially accountable for his
actions. And I think one can see running through the cases that
there is implied … that there must be some form of mental
disease. 65
5.58 Galbraith indicated a major change in judicial approach. The formula in Savage
was not to be read in a narrow sense. It was not necessary that all the criteria in
that formula should be present. Moreover, although the plea had to be based on
some form of mental abnormality, a wide range of conditions could constitute
diminished responsibility and they need not be bordering on insanity. The court in
Galbraith ruled that diminished responsibility required the existence of an
abnormality of mind which had the effect that the accused’s ability to determine or
control his actions was substantially impaired. The court excluded from the scope
of the plea (i) any condition brought on by the voluntary consumption of drink or
drugs and (ii) psychopathic personality disorder. 66
5.59 It formulated the defence as follows:
60 HHJ Robert Taylor.
61 Mr Justice Pitchers stated that he dislikes directions to the jury which “give an undue
normative role to their decisions” and Mr Justice Stanley Burnton stated that he dislikes
any definition that “involves the jury in a value judgment”.
62 Scot Law Com No 195.
63 2002 JC 1.
64 1923 JC 49.
65 Ibid, at p 51.
66 Scot Law Com No 195 para. 3.3.
97