Factors Affecting Liability III – Mental Incapacity
Insanity
A state of mind caused by disease, disorder, or
disturbance (temporary or longstanding), which prevents a person from
knowing the physical nature of an act they are committing or from
appreciating that the act was wrong
An accused bears the onus of proving insanity on the balance of probabilities – Porter (1933)
M’Naghten’s Case (1843)
Decision: Sets out the common law defence of insanity.
Every man is presumed to be sane, & to possess a sufficient degree
of reason to be responsible for his crimes, until the contrary is
proved to the satisfaction of the jury.
It must be proved that at the time of committing the act, the accused
was labouring under such a defect of reason, owing to a disease of the
mind, so as not to know the nature & quality of the act he was
doing, or if he did know it, that he did not know what he was doing was
wrong.
Insanity is a defence to all crimes & results in a full acquittal
However, a person acquitted is found “not guilty by reason of
mental illness” & receives a special verdict under s38 of the
Mental Health (Criminal Procedure) Act 1990 which involves some degree
of therapeutic incarceration
Porter (1933) (High Court)
Facts: The defendant administered strychnine to his infant son &
had then attempted to take the strychnine himself but was interrupted
by police. The child died & the defendant was charged with murder.
He pleaded insanity. There was evidence that he had become extremely
emotional & showed symptoms of a nervous breakdown due to
unsuccessful efforts of reconciliation with his wife.
Decision: It is for a jury to decide whether or not the accused was insane at the time of committing the criminal act.
The state of mind of the accused must be one of disease, disorder or disturbance.
The state of mind must be of such character as to prevent the accused
from knowing the physical nature of the act he was doing or from
knowing that what he was doing was wrong.
An accused may have so little capacity for understanding the nature of
life and the destruction of life that to him it is no more than
breaking a twig or destroying an inanimate object.
Mere excitability of a normal person, passion, stupidity, obtuseness,
lack of self-control, & impulsiveness are quite different from
insanity.
Disease of the mind is a legal term, not a medical one.
Kemp [1957] (Queen’s Bench)
Facts: The defendant was charged with GBH to his wife when he struck
her with a hammer. There was evidence that he was suffering from
arteriosclerosis (a hardening of the arteries) which resulted in a
temporary loss of consciousness when he attacked his wife.
Decision: Arteriosclerosis was a disease of the mind within the
M’Naghten rules & so the defendant was suffering from a defect of
reason.
Whether or not there is sufficient evidence that a particular condition
is a disease of the mind, such that the issue is fit to go to the jury,
is a question of law for the judge.
Quick (1973) (Queen’s Bench)
Facts: The defendant, who was a diabetic, was charged with assault
occasioning actual bodily harm when he assaulted a spastic patient at
the hospital where he worked. He gave evidence that he had injected
himself with insulin, drunk alcohol & eaten little, so that at the
time of the attack he was suffering from hypoglycaemia.
Decision: Insanity within the M’Naghten rules involves a
malfunctioning of the mind caused by disease. Where the malfunction was
caused by some external factor (such as the injection of insulin),
instead of some internal factor (such as the diabetes itself), the
malfunction could not be said to be due to the disease (insanity).
External factors may give rise to a defence of sane automatism whereas
internal factors can only give rise to a defence of insanity (insane
automatism).
• Stapelton (1952) (High Court)
Decision: Where an accused cannot appreciate the wrongfulness of his
act, ‘wrong’ means wrong according to the ordinary principles of
reasonable people, & not wrong in the sense of being contrary to
the law.
• Antisocial personality disorder (psychopathy) does not amount to a disease of the mind (insanity)
Wilgoss (1960) (High Court)
Facts:The defendant was charged with murder when he shot the
deceased during a burglary at the deceased’s residence. He pleaded
insanity. There was evidence that the defendant was a psychopath by his
gross lack of self-control, gross lack of emotional feeling & lack
of conscience. However, he was intellectually capable of knowing his
acts were wrong.
Decision: Defendant was found guilty of murder.
A psychopath may lack an emotional appreciation of the wrongfulness of
an act, but if a psychopath is intellectually capable of knowing his
acts are wrong, he cannot rely on the defence of insanity.
• Irresistible impulse – where an accused knows that what he or she
is doing is wrong, but is unable, owing to a disease of the mind, to
control his or her actions
AG for SA v Brown [1960]
Facts: Brown killed his employer for no apparent reason. He pleaded
insanity, & there was evidence that at the time of the shooting, he
was a schizoid personality & couldn’t help himself because of an
irresistible impulse. He knew the nature & quality of the act but
did not know that it was wrong.
Decision: Irresistible impulse is not a defence. It does not come under
insanity within the M’Naghten rules, though it may go towards arguing
insanity.
• Fitness to plead – an individual who suffers from a mental
impairment of such magnitude as to be incapable of understanding the
nature of the proceedings may be considered unfit to stand trial
Automatism
A state in which the mind or will of a person does
not accompany the person’s actions (i.e. the actions are involuntary)
• Prosecution is entitled to presume that the defendant had
sufficient capacity to act according to an exercise of will – Falconer
(1990)
• Examples include concussion from a blow to the head (Wogandt),
“sleepwalking” (Jiminez), extreme states of intoxication caused by
alcohol (O’Connor, but note Crimes Act 1900 s428G) or drugs (Haywood),
hypoglycaemia (Quick), a sudden illness (Hill v Baxter) or dissociation
caused by a severe psychological blow (Falconer)
Sane automatism – automatism that does not result from a disease of the mind
• Once a defendant has satisfied the evidentiary burden (raised the
possibility that his actions are not voluntary), the onus lies on the
prosecution to prove beyond reasonable doubt that the defendant’s
actions were voluntary
• If successful, results in a complete acquittal
Insane automatism – a condition where the accused is suffering
from a disease of the mind such as to behave in an automatic state
• Proceeds according to the M’Naghten rules
• Onus lies on the defendant to prove insanity on the balance of probabilities
• If successful, results in a verdict of “not guilty by reason of mental illness”
• Recurrence test – if the mental condition is prone to recur, it
should be considered a disease of the mind (insane automatism) – Bratty
v AG (Northern Ireland) [1963]
Internal/external test – if the mental state is internal to the
defendant, as opposed to arising from an external cause, it should be
defined as a disease of the mind (insane automatism) – Falconer (1990)
Falconer (1990) (High Court)
Facts: The defendant was convicted of the wilful murder of her
husband with a shotgun. She gave evidence of a violent marriage &
the discovery that her husband had sexually interfered with her
daughters. On the day of his death, the her husband came home &
sexually assaulted the defendant. She remembered nothing from that
point until she found herself on the floor with a gun by her & her
husband dead on the floor beside her.
Decision: Court formulated an objective standard.
If the psychological trauma suffered by the accused (externally caused)
would have produced a transient dissociative state in the ordinary or
normal person, then it may be regarded as sane automatism.
If, however, it would not produce this state in the ordinary person
then the issue would fail, or the jury should be directed as to
insanity. Here, she was entitled to an acquittal.
Joyce [1970]
Facts: The defendant was charged with murder when he stabbed a girl
to death. At the trial, evidence was given that he was in a state of
dissociation at the relevant time, in which one part of him knew what
he was doing & intended to kill, while the other part of him did
not. He was not suffering from a disease of the mind.
Decision: Court held that where the personality was divided, & one
of the divided parts was conscious of the act & willed it, the
defence of automatism & insanity could not be relied on.
Henessey [1989]
Facts: The defendant, who was a diabetic, failed to take his insulin & then stole a conveyance.
Decision: This amounted to insanity, as his ability & awareness of
what was going on was impaired, & this was caused by an inherent
defect or disease rather than an external factor.
• Self-induced intoxication cannot be raised in relation to an argument of automatism – s428G Crimes Act 1900 (NSW)
Bailey [1983]
Facts: A diabetic failed to take sufficient food after taking
insulin. He caused GBH & his defence was that because of this
failure he was in a state of automatism.
Decision: Court held that self-induced automatism other than due to
intoxication from alcohol or drugs may provide a defence to crimes of
basic intent. The question is whether the prosecution has proved the necessary
element of recklessness. If he does appreciate the risk that (failure
to take food) may lead to aggressive, unpredictable &
uncontrollable conduct & he nevertheless deliberately runs the risk
or otherwise disregards it, this will amount to recklessness.