Introduction
The automatism defence, a critical element in criminal law, pertains to situations where an individual commits an act without voluntary control over their movements. This defence rests on the fundamental principle that criminal liability requires both a prohibited act (actus reus) and a culpable mental state (mens rea). When a person's actions are not directed by their will, they lack the necessary mental element for most criminal offences. Automatism, therefore, constitutes a denial of voluntariness, suggesting the act occurred outside the control of the individual's conscious mind. Successful invocation of this defense requires demonstrating a complete lack of voluntary control, not simply an impairment or reduction. Furthermore, the conditions giving rise to automatism must stem from an external factor, distinguishing it from conditions classified as “insanity” under legal definitions.
Defining Automatism: Loss of Voluntary Control
The essence of the automatism defence lies in the complete destruction of voluntary control. As established in Attorney-General’s Reference (No. 2 of 1992), a landmark case, this defence requires a "total" loss of control over one's actions; partial or reduced control does not suffice. The defendant's actions must occur without their conscious direction, a state where the body acts without the mind's direction. For the automatism defence to be successful, the individual must demonstrate a state where they were not aware of their actions and could not control them. This high threshold means demonstrating more than simply a lack of awareness; it means showing the actions were not the result of conscious decisions or volitional acts. A person merely "driving without awareness", as in the Attorney-General's Reference, does not fulfill this high requirement, as some level of control is still retained. They can react to significant external stimuli. The critical distinction lies in whether the actions result from a voluntary act or an involuntary, automated physical response.
External Factors and the Automatism Defence
The cause of the automatism is crucial. In law, automatism must stem from an external cause, rather than an internal one, to be considered “sane automatism”. An external cause is one which operates outside the individual’s body or mind, like a blow to the head, the administration of certain drugs, or the impact of a traumatic event. This principle is demonstrated in R v Quick, where a diabetic's hypoglycaemic state, induced by insulin intake and failure to eat, was deemed an external factor. Here, it was the medication interacting with the body, not the diabetes itself, causing the automatism. On the other hand, conditions stemming from an internal source fall under the ambit of “insanity” or "disease of the mind". R v Hennessy, clarifies the distinction: a diabetic's hyperglycaemia caused by diabetes itself, rather than an external factor, does not amount to sane automatism. This distinction is critical as it determines the nature of the legal outcome; if the cause of automatism is external, the individual is fully acquitted, whereas an internal cause can result in a verdict of “not guilty by reason of insanity”.
Distinguishing Automatism from Insanity
A vital distinction exists between automatism and insanity, and this distinction hinges on whether the loss of control originates from an internal or external factor. Insanity, a distinct legal concept, arises from a “disease of the mind”, as discussed in R v Sullivan. A disease of the mind encompasses any condition, regardless of its permanence or cause (internal) that affects the mental faculties of reason, memory, and understanding. Conditions such as epilepsy, sleepwalking, and the state of hyperglycaemia mentioned above are categorised as a disease of the mind due to their origin. This classification matters because the legal consequence is substantially different. A successful plea of automatism results in a complete acquittal, acknowledging that the individual’s actions were not voluntary and thus not deserving of criminal responsibility. In contrast, a successful plea of insanity results in a verdict of “not guilty by reason of insanity,” which may result in detention in a psychiatric hospital. R v Burgess confirms this distinction by ruling that sleepwalking is a disease of the mind, owing to its internal, and potentially recurrent nature. Hence, the categorisation of the origin of the automatism as either internal or external has profound legal implications.
Self-Induced Automatism and Criminal Liability
The question of self-induced automatism introduces further complexities. While the automatism defence might be available when triggered by an external factor, it is largely unavailable when the individual's actions caused the state of automatism. R v Bailey makes it clear that a person who has become aggressive because they failed to eat after taking insulin could still be found reckless and liable for their actions. Individuals who knowingly put themselves at risk of exhibiting uncontrollable behaviour cannot escape responsibility for their resulting actions. R v Hardie further clarifies this position: the administration of a sedative drug with an unexpected result may provide a defence. However, if a drug was knowingly taken and caused a state of automatism that resulted in harm, a person cannot evade liability by claiming automatism, except where a sedative was taken without the knowledge it could lead to aggressive or uncontrolled behaviour. This principle stems from a concern that individuals should not be able to avoid liability by intentionally placing themselves in situations where their actions might be unpredictable or harmful.
Examples and Case Applications
Several case studies further illustrate the application of the automatism defence. Hill v Baxter shows the difficulty in establishing a state of automatism. The defendant's claim that he was overcome by an unknown illness while driving did not satisfy the burden of proof for the defence. His actions leading up to the incident were indicative of a state of awareness, not an involuntary state. R v T provides a rare instance where the aftermath of a traumatic experience (rape) was deemed an external factor leading to automatism (PTSD). This case showed that the defence of sane automatism can, in some cases, even apply to non-physical situations, and is a good example of a traumatic external factor. This ruling was dependent on the fact it was deemed "an extraordinary external event that would likely have an appalling effect on the average person". Broome v Perkins demonstrates the need for a complete loss of control: a diabetic driver who veered to avoid collisions was deemed to have retained some control and was thus not considered to be acting in a state of automatism. Finally, Bratty v Attorney General for Northern Ireland clarifies that the burden of proof for automatism rests on the defendant. This means that the defendant must present sufficient evidence that they were acting in a state of automatism, this requires more than simply a claim. These cases highlight how the defence is applied in various circumstances and how the distinction between a state of automatism and other possible scenarios is critically assessed.
Conclusion
The automatism defence in criminal law is a complex legal concept, requiring a complete loss of voluntary control stemming from an external cause to be successful. It highlights the crucial balance between holding individuals responsible for their actions and acknowledging situations where a person's behaviour is not volitional. The distinction between automatism and insanity, between internal and external factors, and the concept of self-induced automatism, are all critical components in determining criminal responsibility. Cases such as R v Quick, R v Hennessy, and Attorney-General’s Reference (No. 2 of 1992) provide the legal framework and practical applications that define this important defense. The law requires clear evidence of a complete lack of voluntary control caused by an external factor to acquit based on sane automatism, reflecting the importance of mens rea in determining culpability.
