R v Byrne [1960] 2 QB 396

KEY POINTS

• ‘Abnormality of Mind’ refers to a state of mind, that is so different to that of an ordinary human being, that a reasonable person would label it as abnormal. The term is wide enough to encompass all aspects of the mind’s activities, including the perception of physical matters and actions, the capacity to determine whether an act is morally right or wrong,  and even the capacity to exercise rational judgment and use willpower to restrain from committing certain physical acts. 

• Manslaughter conviction because of diminished responsibility essentially means that the offender's ability to comprehend the nature of his actions, make reasonable decisions, and/or exercise self-control was significantly impaired, but it is not the same as a finding of insanity where all culpability is extinguished.

FACTS

• The defendant killed a young woman by strangling her and mutilating her body. He stated he committed the crime as he was subject to an overwhelming or nearly irresistible temptation as a result of violent perverted sexual desires that possessed him since he was a youngster. There was evidence that he was a sexual psychopath with very little control over his own actions. 

• The defendant pleaded diminished responsibility as provided under Section 2 of the Homicide Act, 1957, to not be guilty of murder but of manslaughter

• The Trial Court judge ruled that if he was normal but experienced an atypical sexual urge that was difficult to resist on occasion, the "diminished responsibility plea" did not apply. He was found guilty of murder.

• However, The Court of Appeal granted the defendant's appeal on the grounds that the trial judge erred in excluding from the scope of the defense situations in which a defendant was simply unable to control his actions. (This would encompass the scenario of irresistible impulse).

COMMENTARY

• The case on the defendant’s behalf was that he was unable to resist his temptation to commit brutal and sadistic sexual violence. The judge's instructions amounted to exclude his incapacity to control his urges from the definition of mental illness. All of the doctors who examined the defendant agreed that, while the defendant was not insane, he had diminished responsibility.

• It was held that the term "abnormality of mind" was broad enough to encompass all aspects of the mind's activity, including the ability or lack thereof,  to use willpower to regulate physical actions in conformity with reasonable judgment. "Abnormality of mind" refers to a state of mind that is so distinct from that of typical humans that a reasonable person would consider it abnormal. As a result, the defense was able to lower the defendant’s murder conviction to manslaughter.

ORIGINAL ANALYSIS

• A man raped, killed and mutilated a girl and pleaded diminished responsibility so that he should be guilty of manslaughter, not murder.

• The judge directed that if he was normal but on this occassion felt an abnormal sexual impulse that was hard to resist, the “diminished responsibility plea” did not apply.

• He was convicted of murder.

  • Medical evidence said that Byrne was a sexual psychopath whose behaviour became impossible to control when driven by sexual desires, but not under normal circumstances.

  • The Homicide Act 1957 says that the accused must show that he was suffering from an abnormality of mind which was induced by disease, injury retarded development, etc., and was such that it impaired his mental responsibility for his acts in killing/ helping a killing.

• Appeal said that the defendant satisfied these conditions at the time of the murder and the trial judge’s direction was wrong.