1. Topic 8 Insanity

2. Topic 8 Insanity Introduction In order to establish a defence on the grounds of insanity, it must be clearly proved that at the time of committing the act the party accused was labouring under such a defect of reason, caused by a disease of the mind, that he or she either did not know the nature and quality of the act he or she was committing, or did not know that what he or she was doing was legally wrong.

3. Topic 8 Insanity Elements (1) Defect of reason The defendant must show that he or she was suffering from a defect of reason; in other words, that his or her ability to reason was impaired. This is because the basis of the defence is the defendant’s deprivation of the power of reasoning. Thus, a defendant who still possessed those powers but failed to use them cannot be classed as insane.

4. Topic 8 Insanity Elements (2) Disease of the mind In this context, ‘disease of the mind’ is a legal term and not a medical term. This has caused problems at times, since the legal definition does not always match the medical definition. This is apparent when looking at the types of conditions that the courts have accepted as constituting a disease of the mind. Following M’Naghten, delusional states are covered by this, but the inclusion of certain other conditions, such as arteriosclerosis, epilepsy and diabetes, has caused controversy.

5. Topic 8 Insanity Elements (3) Did not know the nature and quality of the act or that the act was wrong The defect of reason caused by a disease of the mind must mean either that the defendant does not know the nature and quality of his or her act or, if he or she does, he or she does not know that the act is legally wrong. In terms of the ‘nature and quality of the act’, the defendant would be unaware of his or her actions. An example that is often given is of a defendant who thinks that he or she is cutting a loaf of bread but who is in actual fact cutting the victim’s throat. If the defendant is aware of what he or she is doing, it is still possible to rely on the defence if he or she does not know that what he or she is doing is legally wrong.

6. Topic 8 Insanity Burden and standard of proof The defendant must prove that he or she was suffering from insanity when he or she committed the offence. This must be proved on the balance of probabilities.

7. Topic 8 Insanity Effect If a plea is successful, it leads to a special verdict, and the defendant will be deemed ‘not guilty by reason of insanity’. Until the introduction of the Criminal Procedure Act 1991, this automatically meant an indefinite hospital stay, but now this only applies to murder. If the defendant is charged with another crime, the judge can make a hospital order, a guardianship order, a supervision and treatment order, or an absolute discharge.

8. Topic 8 Insanity Evaluation (1) The burden of proof rests with the defendant Critics have argued that it is unfair that the burden is on the defendant to prove, on the balance of probabilities, that he or she was suffering from insanity. They say that this undermines the notion that the defendant is innocent until proven guilty by the prosecution.

9. Topic 8 Insanity Evaluation (2) The use of a legal rather than a medical definition Perhaps the major flaw in this defence is that the courts use a legal definition of insanity rather than a medical one. In addition, the legal definition dates from 1843 and fails to take account of the huge medical advances that have occurred since then.

10. Topic 8 Insanity Evaluation (3) The rules are too broad The classification of diabetics, epileptics and sleepwalkers as insane has been criticised for suggesting that those suffering from such conditions are a danger to the public, whereas this is far from the truth in the vast majority of cases. Most people with such conditions are able to control them by taking medication.

11. Topic 8 Insanity Evaluation (4) The rules are too narrow The defence can rule out those who are medically insane if they know the nature and quality of their act or that it is legally wrong but are nonetheless unable to stop themselves from committing it. Thus, those at whom the defence should be aimed are unable to rely on it.

12. Topic 8 Insanity Reform (1) Place the burden of proof on the prosecution The Butler Committee and the Criminal Law Revision Committee have suggested that, since it is part of mens rea, the burden of proof should be reversed and placed on the prosecution rather than the defendant.

13. Topic 8 Insanity Reform (2) A new defence Critics argue that the only way forward is to abolish the M’Naghten rules altogether. Instead, a new defence should be introduced. The Butler Committee suggested that this should apply to defendants with a mental disorder and should result in a verdict of ‘not guilty on evidence of a mental disorder’. This would avoid the defendant being labelled insane. Others suggest that there is no need for such a defence at all and that those suffering from insanity should be dealt with outside the criminal justice system.