At the start of the trial, when the defendant is charged, he is charged on the presumption that he is sane and it is up to the defense to rebut the presumption of sanity i.e. to prove that the defendant is not sane.
In M’Naghten (1843) the defendant attempted to kill the Prime Minister, Sir Robert Peel, and instead shot and killed his secretary Edward Drummond. At the time of the killing the defendant was suffering from insane delusions i.e. a false conception of reality.
It was held that in all instances the jury is to be told that the defendant is presumed to be sane at the time of the crime and this presumption is valid until the defense can prove otherwise and in order for the defense of insanity to be successful it must be clearly proved by way of evidence that the defendant was laboring under such defect of reason due to a disease of the mind that he or she was unable to know the nature and quality of the act.
In 1883 the Trial of Lunatics Act was passed and as per s2(1) of the act: –
“Where in any indictment or information any act or omission is charged against any person as an offence, and it is given in evidence on the trial of such person for that offence that he was insane, so as not to be responsible, according to law, for his actions at the time when the act was done or omission made, then, if it appears to the jury before whom such person is tried that he did the act or made the omission charged, but was insane as aforesaid at the time when he did or made the same, the jury shall return (a special verdict that the accused is not guilty by reason of insanity.)”
Copyright © 2018 by Dyarne Ward