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Insanity and Automatism: The Dysfunctional Defences

Image © Joe Belanger

About The Author

Alexander Barbour (Former Criminal & Environmental Law Editor)

Alex has recently graduated from the University of Birmingham, achieving a First Class Honours degree in Law. His main interests lie in issues concerning human rights, criminal justice and the environment. Alex recently received the Albion Richardson Award from Gray’s Inn to fund the BPTC, which he is currently undertaking at the University of Law, Birmingham.

Prior to the enactment of the Criminal Procedure (Insanity and Unfitness to Plead) Act 1991, the mandatory result of a successful defence of insanity was admission to a mental hospital for an indefinite period. The 1991 Act increased sentencing powers of judges so as to bring insanity in line with unfitness to plead, allowing discretion to choose between a hospital order and supervision order. While this addressed, to a certain extent, the problem of defendants pleading guilty to avoid raising the insanity defence, there is still a long way to go until the defences of insanity and automatism in English law are satisfactory.

The defence of insanity is set out in the M’Naghten Rules, laid down in 1843 by the House of Lords:

to establish a defence on the ground of insanity, it must be clearly proved that, at the time of the committing of the act, the party accused was labouring under such a defect of reason, from 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 he was doing what was wrong.

The defendant bears the burden of proving on the balance of probabilities that he or she is insane, and, if the test is met, the judge returns a special verdict of “not guilty by reason of insanity”.

Automatism is a common law defence available for all crimes. If a person totally lacked control of his body at the time of the offence, and that loss of control was not caused by his own prior fault, then he may plead not guilty and be acquitted. Once raised, so long as there is sufficient evidence, automatism is for the prosecution to disprove beyond reasonable doubt. There is no special verdict for automatism, as the outcome is full acquittal. As the defences of insanity and automatism are so closely related, both being centered on complete lack of capacity, reform of one must involve reform of the other, and most of the problems with the defences stem from the law on insanity.

The M’Naghten Rules have proved difficult to apply in modern times, with the traditionally narrow interpretation of the “defect of reason” element attracting much academic criticism. The term has been interpreted to mean that for the defence of insanity, the defendant’s powers of reasoning must be impaired – a mere failure to use those powers, or momentary lapse of concentration is not enough (Clarke [1972]). The scope of the defence also excludes the inability to control compulsions, which Professor Ashworth believes “should clearly be recognised as part of a reformed mental disorder defence” (Principles of Criminal Law, p145).

The “disease of the mind” element is perhaps the most problematic within the M’Naghten Rules. In modern times it is understood to be an impairment of mental functioning caused by a medical condition, but the courts’ broad interpretation of “disease of the mind” in case law has resulted in conditions such as sleepwalking, epilepsy and, most notably, diabetes being included, despite them not being considered mental conditions by either medical professionals or the lay person.

The law makes an illogical distinction between hyperglaecemic and hypolaecemic episodes, and which defences each type of diabetic episode gives rise to. This illogicality has come about because the courts have, instead of characterising conditions as either mental or physical, made a distinction based on whether the lack of control was caused by an internal or external factor. The cases of Quick [1973] and Hennessy [1989] are commonly cited to show the irregularity in the law.

In Quick, the defendant, a male nurse, inflicted actual bodily harm on a patient as a result of suffering diabetic hypoglaecemia. This type of episode is brought about by an injection of insulin not being balanced out by food, or simply by too much insulin being injected. The trial judge ruled that this constituted insanity, and not automatism, leading the defendant to change his plea to guilty to avoid admission to a mental hospital. On appeal, the Court of Appeal held that as hypoglaecemic episodes are a result of an external factor, namely the injection of insulin, they constitute automatism.

The defendant in Hennessy suffered a hyperglaecemic episode, which, as a result of its effects on his powers of reason, led him to drive his car recklessly while disqualified. This episode occurred because the defendant had not injected insulin for a number of days. The judge rejected that this could constitute automatism as hyperglaecemia is caused by an internal factor (namely the diabetes), therefore coming under the defence of insanity. Hennessy pleaded guilty to avoid admission to a mental hospital.

So why is it necessary for the law to make this distinction? The distinction makes no medical sense and has led to severe injustice in a multitude of cases. Indeed Lord Justice Davis has said that the distinction between internal and external conditions is “illogical, little short of a disgrace and should be abolished”.

A further issue with the internal/external distinction is its portrayal as a dichotomy, when in reality there are some conditions in which internal and external factors may operate simultaneously. An example is sleepwalking – some may be more susceptible to a sleep disorder, but then an external trigger, such as an interruption to sleep, sets it off. What stance would the law take in such a case? It is not clear.

The M’Naghten Rules require a defendant to not know the “nature and quality” of his or her acts. This means the insanity defence is only available if the defendant did not know the physical nature of his or her acts (Codère (1917) 12 Cr App Rep 21). This focus on cognitive questions excludes other problems that might arise as a result of a disease of the mind, such as emotional disorders.

If the defendant cannot satisfy the “nature and quality” requirement, he or she can instead succeed in pleading insanity if “he did not know he was doing what was wrong”. The problems emerging from this element are a result of the unnecessarily narrow interpretation this has been given by the courts. In Windle ([1952] 2 QB 826), Lord Goddard interpreted it as meaning that if the accused knew that what he or she was doing was against the law, the insanity defence would not be available. The effect of such an interpretation has been to close off the availability of the defence to defendants whose mental disorder prevented them from realising their actions could not be rationally justified. When applied to the US case of Andrea Yates, the law gives an implausible outcome.

Yates was a woman with a history of mental illness who drowned all five of her children in a bath. Believing Satan had been conversing with her, she decided she had no choice but to kill her children while they were still innocent to save them from an eternity of torment in hell. Yates knew the nature and quality of her acts, according to the limb as interpreted by Codère, meaning under English law, she would have no defence of insanity.

This begs the question, who is more insane: Yates or Hennessy? The law in its current form says Hennessy, while lay people and medical professionals would answer, commonsensically, Yates.

The law, as demonstrated above, is damagingly out of step with modern medical practices, leading to unwanted and unnecessary stigmatisation of defendants. Terms such as “insanity”, “disease of the mind” and “lunatics” (courtesy of the Trial of Lunatics Act 1883) are not medical terms, clearly. Instead they are archaic legal terms in desperate need of modernisation. Other jurisdictions, such as Scotland, Canada and Australia, have already updated their insanity test to bring it in line with modern-day medicine, so why haven’t we? The reluctance of the UK Government to legislate is creating direct problems in court, with medical professionals and jurors alike being affected by the mismatch of terms. Experts ought not to have to go through the complicated exercise of translating a psychiatric condition into outmoded legal concepts, and the process is even more perplexing for jurors, to whom both sets of terminology will most likely be new.

In an era of Human Rights, it is surprising that the defence of insanity is at such odds with Human Rights law. The leading case of Winterwerp v Netherlands (1979) 2 EHRR 387 laid down clearly the requirement that for the defence of insanity to be human rights compliant, there must be objective medical expert opinion supporting that the accused is of unsound mind. Importantly, it was noted that this relates to the existence or otherwise of a mental disorder, not hyperglaecemia, epilepsy or any of the other questionable conditions currently within the scope of the insanity defence.

The current limitations of the law on insanity are, in practice, leading to cases where ineffective and inadequate treatment is being given to people suffering from serious medical conditions. In Keenan v United Kingdom (2001) 33 EHRR 38 the defendant suffered from serious mental illness, thought to be schizophrenia. He was convicted of assault and sentenced to four months’ imprisonment. He was known to be potentially suicidal and assaulted prison staff. As a result, he was given an extended sentence for breaching prison discipline, and, during this time, committed suicide. The European Court of Human Rights found that a lack of psychiatric input at the hearing led to unsuitable confinement that amounted to a breach of his Article 3 (prohibition of inhumane and degrading treatment) rights. Reform of the law to encourage medical input and medical definitions of mental conditions would undoubtedly save lives, and ensure suitable conditions of confinement for those with serious mental illnesses.

Not only is it adult defendants who are being adversely affected by the incompetence of the insanity defence, but unnecessary harm is also being brought to youth defendants. Article 3(1) of the United Nations Convention on Rights of the Child, ratified by the in UK 1991, states that the best interests of the child shall be a primary consideration in their trial, yet the Law Commission believes the defence and the available disposals are “particularly ill-suited” to dealing with children with mental problems.

The question many ask is, does it really matter? The defences of insanity and automatism are very rarely pleaded (under 15 pleas of insanity per year, according to academic research), and out of these few cases, only a fraction will lead to complications of the nature discussed above. The answer, however, is this does matter, not only because any illogical law that leads to injustice should be rectified, but also because many of the injustices that occur as a result of the insanity defence happen where the defence is not pleaded at all. In some cases there can be disagreements between the police, CPS and clinicians over the level of information required to make a decision, occasionally a legal practitioner will not have sufficient knowledge of the defence to make the right call, and too often it is difficult for counsel to obtain funding for an expert report. The main reason for the rarity of pleas, however, is that practitioners take a pragmatic approach in order to achieve the “correct” outcome in spite of the defences. This is clear evidence of their defectiveness – defendants should not have to avoid a defence designed specifically to protect them.

So what can be done? Proponents of the ‘abolition principle’ argue there should be no defences of insanity or automatism at all. Instead, evidence of a mental disorder for insanity or another factor causing loss of control for automatism should negate the mens rea requirement for an offence, meaning the defendant should then be acquitted, in accordance with general legal principles. My main objection to this, however, is that in cases where the defendant is charged with a strict liability offence, the accused’s mental condition would be irrelevant, and a conviction would result without their mental condition even being considered.

I share the view of the Law Commission and Professor Ashworth regarding the most appropriate way to reform the defences of insanity and automatism. The proposal entails the creation of a new defence of “not criminally responsible by reason of a recognised medical condition”. It would be a much broader defence aimed at decreasing social stigma associated with mental illness and would bring about a new special verdict of “not guilty by reason of a recognised medical condition”. The defence would centre on a complete lack of responsibility. The key feature of this defence is that the lack of capacity arises from a “medical condition”, a phrase that deliberately excludes the word “mental” in order to include physical conditions, such as epilepsy and diabetes, which have been problematic conditions under the current law. A defence of automatism would also be available to cover cases where the lack of capacity is as a result of something other than a medical condition.

These reforms would bring the dysfunctional defences of insanity and automatism in line with medical practices and eradicate the illogical distinctions plaguing the current law. Parliament’s reluctance to act on proposals of the Law Commission is well documented; but, I would argue, with the law in urgent need of reform, this is something we cannot afford to ignore.

Further Reading

Ashworth and Horder, Principles of Criminal Law, (7th Edn, 2013)

Ashworth, ‘Insanity and Automatism: a discussion paper’ [2013] Crim LR 787

Law Commission, Criminal Liability: Insanity and Automatism – A Discussion Paper (2013)

Mackay and Gearty, ‘On being insane in Jersey: Part 1 – The case of Attorney General v Jason Prior’ [2001] Crim LR 560

Mackay and Mitchell, ‘Sleepwalking, Automatism and Insanity’ [2006] Crim LR 901

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Tagged: Criminal Law, Human Rights

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