LAW03: Criminal Law (Offences against the Person) Defences: Insanity

LAW03: Criminal Law (Offences against the Person) Defences: Insanity

M'Naghten (1843) The rules of insanity originate from this case. D suffered from extreme paranoia and thought that he was being persecuted by the Government. D tried to kill Robert Peel (the PM) but killed his secretary instead. Due to the D's mental state he was found not guilty. The decision caused an outcry and the judges were asked to explain their decision. This explanation created the M'Naghten rules... the rules of insanity.

The main rule is... "in all cases every man is presumed to be sane and to possess a sufficient degree of reason to be responsible for his crimes."

The D must then prove that... "he was labouring under such a defect of reason, from a 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." Cases and materials P1

So, 3 elements need to be proved... 1. A defect of reason; 2. This must be a result of a disease of the mind; 3. Causing the D not to know the nature/ quality of his act or that what he was doing was wrong.

Defect of reason The D's powers of reasoning must be impaired. If the D is capable of "reasoning" but fails to use these powers then there is no defect of reason.

Clarke (1972) T h e D w e n t i n t o a supermarket and picked up 3 items. She put them in her bag and then left without paying. D was charged with theft but claimed she had no m e n s re a b e c a u s e s h e couldn't remember putting them in her bag. The D stated she was suffering from absent-mindedness caused by diabetes and depression.

Clarke (1972) The trial judge stated that this was a plea of insanity, so the D withdrew her defence, pleaded guilty and then appealed! T h e C A q u a s h e d t h e conviction. A defect of reason must be more than absentmindedness or confusion.

Disease of the mind "Disease of the mind" is a legal term and not a medical one. It can be a mental disease or a physical disease which affects the mind.

Kemp (1956) T h e D w a s s u f f e r i n g f r o m h a r d e n i n g o f t h e a r t e r i e s (arteriosclerosis) which caused problems in supplying blood to the D's brain. This sometimes caused the D to momentarily lose consciousness. During one of these episodes D attacked his wife with a hammer, causing serious injury. D was charged with a s. 20. D admitted a defect of reason but said it was not caused by a disease of the mind because it was a physical illness and not a mental one.

Kemp (1956) The D was found not guilty by re a s o n o f i n s a n i t y a n d appealed. The CA upheld the decision. The physical illness had affected the D's ordinary mental faculties of memory, reason and understanding and therefore fell within the definition of insanity.

Sullivan (1983) The D had suffered from epilepsy since childhood. The D was known to show aggression towards people who helped him during an epileptic episode. During a visit to a friend's house D injured an 80 yr old man. The trial judge stated he would direct the jury to find D not guilty by way of insanity. So, D pleaded guilty to a s. 47 offence and then appealed.

Sullivan (1983) T h e C A a n d H L b o t h confirmed the decision. The HL stated that the source of the disease was irrelevant. It did not matter if the impairment was "permanent o r t r a n s i e n t a n d intermittent" provided it existed at the time the D did the act.

So, the "disease" can be of any part of the body provided it has an affect on the mind. The disease can be functional - affecting the functioning of the D. For example, schizophrenia, paranoia or manic depression etc. The disease can be organic - a disease of the organs of the body. For example, epilepsy, arteriosclerosis, brain tumours or diabetes etc.

Hennessy (1989) The D was a diabetic who hadn't taken insulin for 3 days. D got into a car (that had been reported stolen) and drove off. D was charged with taking a motor vehicle without consent and driving whilst disqualified. The D had no recollection of taking or driving the car. Diabetes was affecting his mind and came within the definition of insanity.

Burgess (1991) In some instances sleepwalking will fall within the definition of insanity. The sleep-walking was due to an internal cause (a sleep disorder) and so fell within the definition of insanity.

External factors If the D doesn't know what he is doing because of an EXTERNAL FACTOR then this will not be insanity...... But might be automatism.

Quick (1973) The D was a diabetic who had taken his insulin but had not eaten enough. This will cause low blood sugar and can affect the brain. The D, who was a nurse at a mental hospital, assaulted a patient. The CA stated this was not insanity. It was caused by an external factor (the insulin). So, diabetics will be classed as insane if they have not taken insulin but not insane if they have taken insulin but not eaten.

Not knowing the nature and quality of the act or not knowing the act is wrong "Nature and quality" means the physical character of the act. There are 2 ways in which the D may not know this... 1. The D is in a state of unconsciousness/impaired consciousness; or 2. The D is conscious but due to his mental condition he doesn't know what he is doing.

The D may be able to prove 1 of these 2 things because he is... in an automatic state; or suffering from delusions.

If the D does know the nature and quality of his act they may still have a defence if they do not know what they are doing is legally wrong. If the D is suffering from a mental illness but does know both of these things (the nature and quality and that it is legally wrong) then he is not legally insane.

Windle (1952) The D's wife constantly spoke of committing suicide. One day the D gave her 100 aspirins and killed her. The D gave himself up and said "I suppose they will hang me for this." This proved that the D knew what he had done was wrong and he could not use the defence of insanity and was found guilty of murder (and hanged!)

Johnson (2007) The D forced himself into a neighbour's flat and stabbed him. D was charged with wounding with intent. Two psychiatrists stated D was suffering from paranoid schizophrenia and had hallucinations. But both agreed he knew the nature and quality of his act and that his actions were legally wrong. The CA upheld the trial judge's ruling that insanity was not available. They followed the decision in Windle.