Criminal Law 1 Essay Example | Topics and Well Written Essays - 2000 words

Criminal Law 1 - Essay Example The general rule at common law is that when a defendant has caused a victim's death, and has been proved to have had the necessary mens rea for murder, he may be able to avoid a conviction for murder by establishing that he comes within the scope of the defence of diminished responsibility. In such instance, if the defendant succeeds with the defence, his liability is reduced from murder to manslaughter, the sentence for which is at the discretion of the judge. This form of manslaughter is described as "voluntary" because there will have been evidence that the defendant did intend to kill or cause grievous bodily harm bur certain kinds of extenuating circumstances partially excuse his conduct. In the present case, Arnold had recently been diagnosed, but not treated, with severe depression. This is a ground for diminished responsibility. The rule is that if the defendant can prove on a balance of probabilities a defence of diminished responsibility, he will be guilty of manslaughter rather than murder. The statutory basis for the defence of diminished responsibility is set forth in section 2 (1) of the Homicide Act of 1957 which provides. "Where a person kills or is party to a killing of another, he shall not be convicted of murder if he was suffering from such abnormality of mind (whether arising from a condition of arrested or retarded development of mind or any inherent causes or induced by disease or injury) as substantially impaired his mental responsibility for his acts and omissions in doing or being a party to the killing." An abnormality of mind is a state of mind which the reasonable man would consider abnormal. It is thus defined widely. In R v. Byrne (1960) 2 QB 396, the defendant had strangled a young woman and then mutilated her body. He claimed he was subject to an irresistible or almost irresistible impulse because of violent perverted sexual desires which overcame him and had done so since he was a boy. There was evidence that he was a psychopath, and could exercise but little control over his actions. The defence of diminished responsibility was rejected by the trial judge, and the defendant was convicted of murder. The Court of Appeal allowed the defendant's appeal on the basis that the trial judge had been wrong to exclude, from the scope of the defence, situations where a defendant was simply unable to exercise any self-control over his actions. Lord Parker, CJ said: "Abnormality of mind means a state of mind so different from that of ordinary human beings that the reasonable man would term it abnormal. It appears to us to be wide enough to cover the mind's activities in all its aspects, not only the perception of physical acts and matter, and the ability to form a rational judgement whether an act is right or wrong, but also the ability to exercise will power to control physical acts in accordance with the rational judgment. According to the commentaries of Clarkson and Keating (2003), diminished respon