Discuss whether the rules governing insanity as a defence in criminal law are in a satisfactory state or are in need of reform.

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Q3 Discuss whether the rules governing insanity as a defence in criminal law are in a satisfactory state or are in need of reform. [50]  

Insanity is a complete, general defence. A complete defence is where the mens rea is completely removed from the crime; mens rea is Latin for ‘guilty mind’ and refers to the definition of a  crime that deals with what the defendants state of mind must have been to be guilty for example Murder, the mens rea of it is the intent to kill or do GBH.. The general part of insanity Is something which can be used for any crime. Insanity is also known as insane automatism and the Criminal Procedure Act 1991 gives the outlines for the defendant who is found not guilty by way of insanity. Insanity cannot count as a defence to strict liability crimes such as speeding and these are crimes which are less serious and don’t have a mens rea. At any time throughout the trial the defence for insanity can be called upon by any member of the defence or prosecution. If a claim for insanity is successful then the defendant will end up with a verdict of not guilty however they will have to go to a mental hospital to prevent further danger to themselves and other people. If there is an unsuccessful claim of insanity then the defendant may be found guilty and therefore go to prison etc, or he may be fully acquitted.

Whether the defendant can be classed as insane and win an appeal depends on the 4 rules set out by the M’Naghton test. M’Naghton was a man who was mentally unstable and in 1943 killed the prime ministers secretary instead of the prime minister after suffering from a condition known as severe paranoia which clouded his judgement. In this case he was successfully labelled as insane which meant he was able to give a plea of insanity and this led to a not guilty verdict. From this case the M’Naghton test was established meaning that to qualify as insane any one defendant must suit the following:

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  1. The defendant must have disease of the mind.
  2. The defendant must have defect of reason.
  3. The defendant did not know the nature and quality of the act he was committing. OR
  4. The defendant did not know that his actions were legally wrong.

The first rule is that the defendant must have ‘disease of mind’ but here we are not talking about the medical definition. The cause of the disease of mind must be internal meaning that the likes of brain tumours don’t count. The internal part of the rule means that there should be a malfunctioning of ...

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The student addresses the disease of the mind aspect of the offence, and related criticisms, well. To improve the essay, reference could be made to presumption of sanity and burden of proof; the issue of the "nature and quality of the act"; and knowledge that the act was wrong. Three stars.