Transcript Voluntary Manslaughter

Diminished Responsibility
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The Homicide Act 1957 s2(1) provides a
defence where D:
‘...was suffering from such abnormality of
mind (whether arising from a condition of
arrested or retarded development of mind or
any inherent causes or induced by disease or
injury) as substantially impaired his mental
responsibility for his acts and omissions in
doing or being a party to the killing.’
Voluntary manslaughter: diminished responsibility
Effect
Diminished responsibility is a partial defence, which
applies only to murder. If pleaded successfully, it will
reduce the defendant’s liability from murder to that of
manslaughter and thus allow him or her to avoid the
mandatory life sentence.
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The defences ONLY apply to murder
They reduce it to manslaughter
This means the sentence is at the judge’s
discretion
Circumstances can be taken into account
The burden of proof is on the defendant to
prove diminished responsibility on the
balance of probabilities
Voluntary manslaughter
Introduction
Voluntary manslaughter was introduced by Parliament via the
Homicide Act 1957. It was designed to cover the situation
where the defendant has both the actus reus and mens rea of
murder but the surrounding circumstances of the offence
mean that the defendant’s liability is reduced from murder to
manslaughter. These relevant circumstances amount to
partial defences specific to a murder charge and are defined
by the Homicide Act as diminished responsibility,
provocation and suicide pacts.
Voluntary manslaughter: diminished responsibility
Definition
Diminished responsibility is defined in s.2 of the Homicide
Act 1957:
‘Where a person kills or is party to a killing of another, he
shall not be convicted of murder if he was suffering from
such abnormality of mind (whether arising from a
condition of arrested or retarded development of mind or
any inherent causes or induced by disease or injury) as
substantially impaired his mental responsibility for his acts
and omissions in doing or being a party to the killing.’
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Replaces section 2(1) of the Homicide Act
with new subsections (1) to (1B)
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1.
2.
3.
The ‘abnormality of mind’ as expressed in the 1957
Act is replaced by the words ‘abnormality of mental
functioning’ in the new Act.
This abnormality of mental functioning must:
A) arise from a recognised medical condition
B) substantially impair the defendant’s ability to do
one or more of the following:
Understand the nature of his conduct
Form a rational judgment
Exercise self control
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The abnormality of mental functioning
provides an explanation of the defendant’s
conduct if it causes, or is a significant
contributory factor in causing, the defendant
to act as he did
A defendant who puts forward this defence
must prove it on the balance of probabilities
Under the 1957 Homicide Act ‘abnormality of
mind’ has been held to cover many different
kinds of medical condition, such as:
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Psychotic disorders – Byrne (1960)
Clinical depression and epilepsy
Post -natal depression – Reynolds (1988)
PMT (Pre-menstrual tension) – English (1981)
BWS (Battered wife syndrome) – Ahluwalia
(1992)
The C&JA 2009 recognises that there are many
existing lists which classify accepted physical,
psychiatric and physiological conditions – foremost is
the:
World Health Organisation’s international
classification of diseases
American Psychiatric Association’s diagnostic and
statistical manual of mental disorders
If a jury accepts that, at the time of the killing, a
defendant was suffering from a condition included in
one of these lists then the test above will be met.
If there is a new or emerging condition that is not on
the list, a validated specialist can be called to give
evidence.
The Homicide Act 1957 required that a
person’s mental responsibility must be
substantially impaired, but it did not specify
in which way.
The Coroners and Justice Act 2009 attempted
to clarify this.
The abnormality of mental functioning has to
be a significant contributory factor in causing
the defendant to act as he did. It need not be
the only cause, the main cause, or the most
important factor.
It must however, be more than merely trivial.
There must be a causal (not casual!)
connection between the abnormality and the
killing in order for the defence to succeed.
The defence should not be able to succeed
where the defendant’s mental condition made
no difference to his behaviour; that he would
have killed regardless. (apply this point to
Gittens, and Dietschmann)
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Abnormality caused by drink or drugs would
not usually be accepted
There may be an exception if the abnormality
is caused by the disease of alcoholism
But not by the voluntary taking of alcohol
See Tandy
Why did the defence fail?
It is more difficult where D is intoxicated in
addition to suffering from one of the stated
causes as in Dietschmann
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Read the case of Dietschmann carefully
The Court of Appeal were unsure about how
the law should apply
The case went to the House of Lords for
clarification
What did the House of Lords decide?
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Can you comment on the problems with this
issue?
It is very difficult for the jury
They must try to decide if the abnormality would
have substantially impaired D’s mental
responsibility regardless of the intoxication
It may be hard to disentangle the two if D was
affected by both intoxication and another ‘cause’
The effect of drink can contribute as long as the
other ‘cause’ played a more than trivial part in
impairing D’s responsibility
The law is not very clear on this
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The defence has been raised in many
different circumstances based on a wide
range of causes, from Gulf War syndrome to
pre-menstrual tension
In Martin, although self-defence failed, he
succeeded in arguing diminished
responsibility as he had a ‘paranoid
personality disorder’
In several ‘mercy’ killing cases the defence
has succeeded - see case study
The
requirements
are:
Which
substantially
impairs D’s
responsibility
or an
inherent
cause or
disease or
injury
An
abnormality
of mind
Caused by
arrested or
retarded
development
of mind
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The burden of proof is on the defendant
rather than the prosecution
The wording of the Homicide Act is unclear
Medical evidence has moved on since 1957
It can also be complex and confusing for the
jury
It is often contradictory
The jury may ‘find’ diminished responsibility
where they feel there is moral justification for
the killing (as in euthanasia cases)
Voluntary manslaughter: diminished responsibility
Burden and standard of proof
The defendant must prove, on the balance of probabilities,
that he or she was suffering from diminished responsibility
at the time of the killing. Medical evidence will be required
from at least two experts in order to substantiate any such
claim.
Voluntary manslaughter: diminished responsibility
Evaluation (1)
The Law Commission recently reviewed the area of voluntary
manslaughter in its paper ‘Partial Defences to Murder’
(Consultation Paper No 173).
Meaning unclear
Critics argue that it is unclear precisely what the term
‘diminished responsibility’ means. There is little to assist in
determining what constitutes an ‘abnormality of mind’ – it is
simply and tautologically defined as a state of mind that is
‘abnormal’. There are also difficulties in trying to determine
whether the defendant’s mental responsibility has been
‘substantially impaired’.
Voluntary manslaughter: diminished responsibility
Evaluation (2)
Burden of proof rests with the defendant
Opponents of the current law say that the burden of proof should
be changed so that the onus is on the prosecution.
Labels those in abusive relationships as mentally
abnormal
In order to rely on the defence of diminished responsibility,
those in abusive relationships who kill their abusers must claim
to be mentally abnormal. Critics say that this should not be the
case and far more emphasis should be placed on the abuse that
they have suffered rather than their state of mind.
Voluntary manslaughter: diminished responsibility
Evaluation (3)
Courts too ready to accept the defence in some cases
The courts have been criticised for being too willing to accept
the defence of diminished responsibility in some instances. In
some cases involving euthanasia, the courts may take the
view that the defendant does not deserve to be labelled a
murderer and face the accompanying life sentence, and so
accept a plea of diminished responsibility on the basis of little
evidence. Despite their good intentions, this is seen by many
as a misuse of the defence.
Voluntary manslaughter: diminished responsibility
Reform
In its recent review, the Law Commission found that there
had been a fall in the successful use of the diminished
responsibility defence. However, it stated that the defence
appeared to be working and advocated its retention as
long as the mandatory life sentence for murder remains.
No radical changes were proposed.