The Insanity Defence

Insanity "disease of the mind" is a legal term for mental illness causes of such degree that the individual is not responsible for his or her acts. In most criminal jurisdictions (in UK and US), a degree of mental malfunctioning considered to be sufficient to relieve the accused of mental responsibility for the act committed. The rules on insanity are based on the M`Naghten Rules of 1843. The M`Naghten rule on criminal insanity is named for Daniel M`Naghten, who, in 1843, tried to kill England`s Prime Minister Sir Robert Peel. He tried to shoot Peel but instead shot and killed Peel`s secretary, Edward Drummond. Medical experts testified that M`Naghten was psychotic, and M`Naghten was found not guilty by reason of insanity. [9] The main rule on insanity is that ". every man is presumed to be sane and to possess a sufficient degree of reason to be responsible for his crime." Under the M`Naghten rule a criminal defendant is `not guilty by reason of insanity` if at the time of the committed act he was "deranged such that he did not know the nature and quality of his actions, or, if he did know it that he did not know he was doing what was wrong." [10] The US definition of insanity is a deranged state of the mind usually occurring as a specific disorder [11]; such unsoundness of mind or lack of understanding as prevents one from having the mental capacity required by law to enter into a particular relationship, status, or transaction or as removes one from criminal or civil responsibility. In the UK insanity is decided by the judge during the trial [12]. The verdict "not guilty by reason of insanity" can only be given by the jury when two or more doctors have given evidence supporting the defendant`s claim, at least one doctor must be approved by the Home Secretary as having expertise in the field of the disorder. In the US, in some states sanity can be determined by the judge or jury [13]. Unlike in the UK where sanity is determined during the trail or pre-trial before the verdict, in some stated in the US sanity is determined in a separate proceeding following the determination of guilt or innocence at the trial. In other states, the defence is either accepted or rejected in the verdict of the judge or jury. [14] In the Crown Court, for the verdict of not guilty by reason of insanity to be given, the prosecution must prove that the accused "did the act or made the omission" [1]. This means that the prosecution have to prove "the ingredients which constitute the actus reus", and are not required to prove any mental element (mens rea). The mens rea is to be proven by the defence. If the defence of insanity is won in court, the defendant receives a special verdict from the judge. This only happens when the defendant wins the pleas of not guilty by reason of insanity