Insanity Defences Flashcards
DEFINE LEGAL INSANITY
Section 23 - Crimes Act 1961
(2) No person shall be convicted of an offence by reason of an act done or omitted by him when labouring under natural imbecility or disease of the mind to such an extent as to render him incapable—
(a) Of understanding the nature and quality of the act or omission; or
(b) Of knowing that the act or omission was morally wrong, having regard to the commonly accepted standards of right and wrong.
BURDEN OF PROOF
Burden of proof on defence to prove defendant was insane on balance of probability.
If defence can’t prove but jury still thinks defendant is insane he can be acquitted on the grounds of insanity.
CASE LAW: R V COTTLE
As to degree of proof, it is sufficient if the plea is established to the satisfaction of the jury on a preponderance of probabilities without necessarily excluding all reasonable doubt.
Evidence of insanity
Insanity is a legal question, not a medical one. However, the question of whether or not the defendant is legally insane is usually addressed by evidence from medical experts called by defence and crown.
Case Law: R v Clark
The decision as to an accused’s insanity is always for the jury and a verdict inconsistent with medical evidence is not necessarily unreasonable. But where unchallenged medical evidence is supported by the surrounding facts a jury’s verdict must be founded on that evidence which in this case shows that the accused did not and had been unable to know that his act was morally wrong.
M’NAGHTEN RULES - TEST FOR INSANITY
The rules are used to establish whether or not a defendant is insane. It is based on the persons ability to think rationally so that if a person is insane they were acting under such a defect of reason from a disease of the mind that they did not know:
- the nature and quality of their actions or
- that what they were doing was wrong
Case Law: R v Codere
The nature and quality of the act means the physical character of the act. The phrase does not involve any consideration of the accused’s moral perception nor his knowledge of the moral quality of the act. Thus a person who is so deluded that he cuts a woman’s throat believing that he is cutting a loaf of bread would not know the nature and quality of his act.
