Criminal Liability: Insanity and Automatism

download print

About this sample

About this sample


Words: 1614 |

Pages: 4|

9 min read

Published: Nov 15, 2018

Words: 1614|Pages: 4|9 min read

Published: Nov 15, 2018

Table of contents

  1. Insanity and Automatism under UK Jurisdiction
  2. Insanity and Automatism Commonalities
  3. Discussion
  4. Conclusion

In law, there are two major theories that describe and justify punishment: utilitarianism according to which punishment should be given to avoid further harm and retributivism which comes in to ensure that there is justice. Defenses ensure that individuals who never freely commit a crime are not punished, particularly in cases where the actions of the defendant are were influenced forcefully or were involuntary. All the above defenses are in one way or another connected to mental disorders. Insanity and automatism play a crucial role in these cases as they present defenses and excuses for the failure of proof. As such, they are important in court cases where the defendant’s mind is confirmed to be abnormal at the time of committing the crime. The nature of brain illness is of irrelevance so long as the mental faculties of understanding, memory, and reasoning were impaired when committing the offense. If the defendant was aware of the kind of offense he committed, then insanity may be applied as a valid defense. Where there is cognitive awareness, it may function to oppose the actus reus and mens rea in the criminal justice system. This paper seeks to examine the commonalities in these two defenses that make them inseparable and therefore no need to have them as separate entities.

'Why Violent Video Games Shouldn't Be Banned'?

Insanity and Automatism under UK Jurisdiction

Insanity shares commonalities and difference with automatism concerning their description, application, and their results as defenses. The courts usually use their differences to make decisions on which defendant to release or not. This is essential because of the defenses if successful, have different results for the suspect. For instance, where automatism defense is successful, the case may be acquitted, insanity, on the other hand, may result in a special verdict of not being guilty. Judges have had a difficult time trying to make distinctions between the two defenses. Sometimes the defendant may plead automatism only for judges to replace it with insanity and vice versa (Mackay RD1995).

Before the Criminal Procedure Act was enacted in 1991, the obvious result for any successfully concluded insanity defense was being admitted to a mental hospital indefinitely. The new act handed more powers to the judges to give options for defendants to either choose hospital order or supervision order. This to some extent solved the issue of the accused pleading guilty as a way of avoiding insanity defense being brought forward. In 1843, the House of Lords presented M’Naghten Rules of insanity defense which stated: "to establish a defense on the ground of insanity, it must be clearly proved that, at the time of the committing of the act, the party accused was laboring 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".(Glazebrook PR, 2010)

Insanity and Automatism Commonalities

This act further expanded the powers of judges to offer several options after insanity verdict that includes: guardian order, treatment/absolute discharge order, and supervision order. Thus the first element to be considered is whether or not the defendant knew the nature of the crime he carried out and if he was able to control it. The accused has the burden to prove to the courts that he or she has a mental disorder. The test must be met for the courts to consider the verdict of ‘not guilty by insanity'. This also constitutes the second element of the accused having a defect that changes the power of reason. Similarly, automatism defense considers the state of mind of the defendant at the time of the crime.

Automatism is defined by Lord Denning as "an act which is done by the muscles without any control by the mind such as a spasm, a reflex action or a convulsion, or an act done by a person who is not conscious of what he is doing such as an act done whilst suffering a concussion or whilst sleepwalking" (Mackay RD1995). Where the defense is successful, it leads to the acquittal of the case as no verdict can be made from automatism.

Thirdly, the two defenses involve denying either the mens rea (mental status) or the actus reus (a forbidden act). Of course both insanity and automatism are defenses made to lessen the strength of judgment expected to be made. Lastly, they both involve cases where the defendant is infected with a disease of the mind. A defect of mind should be caused by an internal source that can be Sleepwalking or Epilepsy. Implementation of M’Naghten’s rules has been problematic in the modern era with academic criticism of the traditional narrow definition. More especially, application of the element of "disease of the mind" has proved difficult. This is because it has been understood to be a mental impairment that is caused by a certain medical condition. But the courts have a broad interpretation that constitutes conditions such as epilepsy, sleep working, and now the inclusion of the most controversial, diabetes despite not being recognized as a mental condition by medical professionals.

The disease of mind is hence limited to mental disorder, and it's any factor that affects and alters functioning and reasoning of the mind. Mind, in this case, is the mental faculties that help individuals to reason, understand, and memorize. As described by the Lord Diplock, what is of importance to the courts is the effect of the impairment: "If the effect of a disease is to impair these faculties so severely as to have either of the consequences referred to in the latter part of the rules, it matters not whether the etiology of the impairment is organic, as in epilepsy, or functional, or whether the impairment itself is permanent or is transient and intermittent, provided that it subsisted at the time of commission of the act". (Jowell and McAuslan, 1984)

Diabetic individuals who fail to take prescribed medication risk suffering hyperglycemia thus insanity. Those to suffer serious reactions from the medication fail to reason because of external factors, which is the medication, in this case, they fall under automatism. These two conditions make no medical difference as the state of mind as they both involve failure of reason. The law, on the other hand, makes no logical distinction between hypoglycemic and hyperglycemic episodes of diabetes and the type of defenses each is expected to give rise to. This is because instead of judges making distinctions based on mental or physical conditions, the law directs them to make the differences based on if the individual’s lack of reason or control was influenced by internal or external factors.

Taking an example of the case of Quick (1973), a diabetic patient suffering hypoglycemic episode caused bodily harm inflicted by the nurse. This is a condition caused by injection of insulin without proper balanced diet or injection of too much insulin. The court ruled out that this constituted insanity, in response, the accused changed his plea to guilty as a way of avoiding to be admitted to a mental hospital. When the case was appealed, the Court of Appeal ruled that the case constituted automatism as the patient was suffering hypoglycemic episodes that are caused by an external factor (injected insulin). This proves that the distinctions that the courts try to uphold make no medical sense and many individuals have suffered injustice as a result. Even Lord Justice Davis agrees that the distinction between external and internal factors is simply illogical. So why then do the courts see it necessary to make the distinctions while some of them work simultaneously like sleepwalking? Do they matter as both the insanity and automatism defenses are rarely pleaded?


The law as practiced above is damagingly and out of step with any medical profession causing stigmatization of the defendants. Terms such as the ‘disease of mind’, ‘insanity’, and in some cases ‘lunatics’ are just legal terms as a way of modernization in this era, not medical terms. Some jurisdictions such as Canada, Scotland, and Australia have tried to make changes in the law of insanity to make it acceptable under medical terms. The defendants’ decisions to avoid this two defenses that are meant to protect their rights is a clear indication that they have proved to be defective.

Some elements of ‘abolition principle’ suggest that insanity defense and automatism defense should be deleted from the law. That since the defenses contradict the mens rea required for an action to be called an offense, he or she should be acquitted according to the law. However, this argument inconclusive in some cases carries strict liability offense where the excuse for mental illness will be considered irrelevant. In this case, the court makes a conviction without consideration of the defendant's mental condition. To my view, the best way to reform and make useful the defenses of insanity and automatism will be the creation of a much broader defense that can incorporate the two defenses with the aim of decreasing stigmatization associated with mental disorders. This will also present a new verdict of "not guilty because of a recognized medical condition".

Get a custom paper now from our expert writers.


Insanity defense and automatism defense as constituted will bring more injustices and stigma rendering them dysfunctional. The reforms should bring the defenses in line with accepted medical terms and practices. It should be treated with urgency as this is simply something we cannot ignore no matter how small the percentage of these cases is. I advocate for the incorporation of the two defenses to one strong defense to avoid confusion brought about by distinctions that do not make sense even in the medical profession.

Image of Dr. Oliver Johnson
This essay was reviewed by
Dr. Oliver Johnson

Cite this Essay

Criminal Liability: Insanity and Automatism. (2018, October 26). GradesFixer. Retrieved February 21, 2024, from
“Criminal Liability: Insanity and Automatism.” GradesFixer, 26 Oct. 2018,
Criminal Liability: Insanity and Automatism. [online]. Available at: <> [Accessed 21 Feb. 2024].
Criminal Liability: Insanity and Automatism [Internet]. GradesFixer. 2018 Oct 26 [cited 2024 Feb 21]. Available from:
Keep in mind: This sample was shared by another student.
  • 450+ experts on 30 subjects ready to help
  • Custom essay delivered in as few as 3 hours
Write my essay

Still can’t find what you need?

Browse our vast selection of original essay samples, each expertly formatted and styled


Where do you want us to send this sample?

    By clicking “Continue”, you agree to our terms of service and privacy policy.


    Be careful. This essay is not unique

    This essay was donated by a student and is likely to have been used and submitted before

    Download this Sample

    Free samples may contain mistakes and not unique parts


    Sorry, we could not paraphrase this essay. Our professional writers can rewrite it and get you a unique paper.



    Please check your inbox.

    We can write you a custom essay that will follow your exact instructions and meet the deadlines. Let's fix your grades together!


    Get Your
    Personalized Essay in 3 Hours or Less!

    We can help you get a better grade and deliver your task on time!
    • Instructions Followed To The Letter
    • Deadlines Met At Every Stage
    • Unique And Plagiarism Free
    Order your paper now