Defences
When someone is charged with an offence there are various different defences that may be available to them. These defences are Insanity, Automatism, Intoxication, Mistake, Self-Defence and Consent.
Insanity
Insanity is available to all offences where Mens Rea is required. It is not available for strict liability offences where no mental element is required. The legal definition of insanity is not the same as the medical definition. It is not common for defendants to plead insanity because most insane defendants are hospitalised under the mental health act before they go to trial. The legal definition of insanity arose from the case of M'Naughten (1843). From the definition it can be seen that three elements need to be proved. These are 1.) There must be a defect of reason. This means that the defendant’s powers of reasoning must be impaired. This does not cover absent-mindedness or confusion. 2.) This must be the result of a disease of the mind. This disease can be a mental disease or a physical disease which affects the mind (Kemp 1956). It covers conditions such as epilepsy and sleepwalking, as long as the sleepwalking is due to an internal factor. 3.) This must cause the defendant not to know the nature and quality of his act, or not to know he was doing wrong. There are two ways in which the defendant may not know the nature and quality of his act, and these are a.) because he is in a state of unconsciousness or impaired consciousness; or b.) where he is conscious but due to his mental condition he does not understand or know what he is doing.
Automatism
There are two types of automatism, insane automatism and non-insane automatism. Insane automatism is where the cause of the automatism is a disease of the mind within the M'Naughten rules. In such a case the defence is insanity and the verdict is not guilty by reason of insanity. Non-insane automatism is where the cause is an external one, and when the defence succeeds it is a complete defence and the defendant is not guilty. This is a defence because the defendant does not voluntarily do the Actus Reus and does not have the Mens Rea for the defence. The cause of the automatism must be external, for example, a blow to the head, an attack by a swarm of bees or sneezing. The loss of control must be total (A-G's reference (No 2 of 1992) (1993). Any indication that the defendant has thought about his actions will cause his defence to fail (Bailey 1983). When a defendant allows himself to get into an automative state it is called self-induced automatism. When the self-induced automatism is caused through drink or drugs or other intoxicating substances the defences cannot use automatism (Majewski 1977). When the defendant does not know that his actions might lead to a self induced automatic state in which he may commit an offence, he has not been reckless and can use the defence of automatism.
