Automatism may be broken down into two parts: (1) insane automatism and (2) non-insane automatism.

 

Non-Insane Automatism

 

Non-insane automatism is unconscious involuntary conduct caused by some external factor where there is no claim of insanity. In general, the defence requires the defendant though capable of action is not conscious as to what he is doing. It applies in cases, for example, where the defendant has performed an involuntary movement or action as a result of “some failure of the mind not due to disease” (Archbold Criminal Pleading Evidence and Practice 2013 Ed. para.17:84). Where the defendant can demonstrate that his or her actions were involuntary precipitated by some external factor, he or she will have a complete defence and will be acquitted. Where the defence of automatism is raised by the defence, it is the prosecution who must disprove it by showing that the acts were voluntary and that the defendant was conscious in carrying them out (R v Stripp (1979) 69 Cr App R 318).

 

Three requirements must be met: (1) there must be an involuntary act; (2) the involuntary act must have been caused by an external factor; (3) the automatism must not be self-induced.

 

Involuntary Act

 

In Hill v Baxter [1958] 1 QB 277, the defendant was driving along when suddenly he was attacked by a swarm of bees, causing him to swerve into other cars. The defendant contended that his action was a reflex and that his actions was involuntary. The court concurred with such an argument and the defendant was not criminally liable.

In Bratty v Attorney-General for Northern Ireland (1963) it was held that:

 

No act is punishable if it is done involuntarily: and an involuntary act in this context - some people nowadays prefer to speak of it as 'automatism' - means an act which is done by the muscles without any control by the mind such as a spasm, reflex action or a convulsion; or an act done by a person who is not conscious of what he was doing … [however] to prevent confusion it is to observed that in the criminal law an act is not to be regarded as a voluntary act simply because the actor does not remember it … nor is an act to be regarded as involuntary simply because the doer could not control his impulse to do it.

 

In Broome v Perkins (1987) 85 Cr. App. R. 321 it was held that a defendant will not be able to rely on the defence of automatism where his control is limited. The accused was in a hypoglycaemic state and, during this time, drove erratically from work, hitting another car. He could not remember anything about the journey. He argued automatism. However, his defence argued due to the evidence showing that he had exercised conscious control over his movements by steering his car away from other vehicles.

 

The decision in Broome v Perkins was considered harsh, however, was followed in Attorney-General’s Reference (No 2 of 1992) [1993] 3 WLR 982. The accused was driving a lorry down the motorway when he crashed into a car parked on the hard shoulder, subsequently killing two people. Experts stated that he had been put into a trance-like state by repetitive vision of the long flat road which reduced, but did not remove, what he was doing. The defendant was acquired, however, in the Court of Appeal it was held that the trial court was wrong and that driving without awareness is not as a matter of law a state capable of founding a defence of automatism.

 

External Cause

 

A distinction must be drawn between sane automatism (which is caused by an external factor) and insane automatism (which is caused by an internal factor).

 

In cases involving an internal factor, or an internal disease of the mind, the courts have stated that is insanity. It is important to distinguish this. Cases which the defendant has held to be insane include epilepsy (R v Sullivan [1984] A.C. 156) or where a defendant suffers from a sleep-related disorder (R v Burgess [1991] 2 Q.B. 92), both of which were held to be precipitated by internal factors.

 

 

In R v Hennessy [1989] 1 W.L.R 287, the accused’s hyperglycaemia was triggered by an internal factor (his diabeties) and therefore within the legal definition of insanity. However, this should be contrasted with the judgment in R. v Quick (William George) [1973] Q.B. 910, where the accused’s hypoglycaemia was caused by insulin and the fact that he had failed to eat property. As these were external factors, he could raise the defence of automatism.

 

Self-induced automatism

 

 

Where the automatism is caused by the defendant’s own fault, then the defence will not be available.

 

In R. v Bailey (John Graham) [1983] 1 W.L.R. 760, the defendant was a diabetic and attacked and injured his ex-girlfriend’s new boyfriend during a bout of hypoglycaemia. The defendant had eaten some sugar but no other food beforehand, as he was unwell. The Court of Appeal held that self-induced automatism, other than that due to intoxication, may provide a defence if the defendant’s conduct does not amount to recklessness. In this case, if the defendant was aware that by failing to eat that it would put him into a state and attack someone without realising It, he was reckless and the defence will not be available.

 

 

In situations where a defendant has taken a drug for their soporific or sedative effect, and they go on to commit a crime involuntarily, the defence may be available, providing that they can demonstrate that their reaction to the drug was unexpected. In R v Hardie [1985] 1 WLR 64 it was held that a defendant who relied on automatism due to taking Valium could rely on the defence, despite the fact that a doctor had not prescribed him the drug.

 

 

Insanity

 

 

The rules for insanity deive from the seminal jugdment in R v M'Naghten [1843] UKHL J16, where it was held that the defence of insanity is available where at the time of the act or ommission giving rise to the offence, the defendant was (1) labouring under a defect of reason; (2) owing to a disease of the mind; (3) so as not to know the nature and quality of his act; and (5) if he knew this, so as not to know that what he is doing was wrong.

 

Defect of reason

 

The defence of insanity is not available to a person who retains the power of reasoning, but who in a moment of confusion or absentmindedness fails to use that power to the full (R v Clarke [1972] 1 All ER 219). 

 

Disease of the mind 

 

It does not matter whether the disease had a mental or physical origin. Likeiwse, whether it is tranistory or non-transitory is immaterial for the defence.  Disease of the mind has held to include: arteriosclerosis (R v Kemp (1957) 1 QB 39); epileptic seizure (R v Sullivan [1984] AC 156); hyperglycaemia caused by inherent defect (R v Hennessy [1989] 2 All ER 9; and sleepwalking (R v Burgess [1991] 2 QB 92). 

 

It should be noted, however, that a malfunctioning of the mind caused by an external factor such as alcohol is not a disease of the mind (R v Paddison [1973] QB 910). Where the defendant has amental condition which is aggrivated by external factors so that the defendant has a defect if reason such that he does not know that the act is wrong, this does not render it a disease of the mind (A-G for Northern Ireland v Gallagher [1963] AC 349; R v Roach [2001] EWCA Crim 2698. In R v Harris [2013] EWCA Crim 223, [2013] All ER (D) 06 it was held that blackouts due to smoking cannabis do not constitute disease of the mind.

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The defect of reason must be such that the defendant did not know what he was doing or, if he did know, he did not know the act was wrong.

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In general, a person knows than an act is wrong if he knows that it is contrary to law. In R v Codère (1916) 12 Cr App Rep 21, CCA, Lord Reading CJ stated that the test is whether the act is right or wrong according to the standard accepted by reasonable men. 

 

In R v Windle [1952] 2QB 826, the appelant killed his wife. Medical evidence demonstrated that he was suffering from a mental defect at the time of the crime. However, when the defendant was arrested, he stated to the police, "I suppose they will hang me for this". The judge held that as the defendant knew what he was doing was wrong, he was not entitled to rely on the defence. 
 

In R v Johnson [1989] EWCA Crim 289, the defendant knew his actions were legally wrong but did not believe them to be morally wrong: because he knew they were legally wrong he was not entitled under the M'Naghten Rules to ask the jury to enter a verdict of not guilty by reason of insanity.

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Sentincing

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Where the jury finds insanity is made out, the verdict takes to be given is not guilty by reason of insanity ( Trial of Lunatics Act 1883 s 2(1) (amended by the Criminal Procedure (Insanity) Act 1964 s 1).