This case clarifies the law on causation in homicide where medical treatment may contribute to the victim's death. It establishes that even if medical negligence is the immediate cause of death, the original assailant can still be criminally responsible, provided their acts contributed significantly to the death. The jury need not determine the “main” cause, only that the defendant’s actions were a substantial factor. 

On 9 December 1987, the appellant shot the victim, Trevor Jeffrey, in a fish and chip shop. The victim sustained severe gunshot injuries to his thigh and abdomen and was taken to hospital, where he underwent surgery and intensive care, including a tracheotomy. Complications arose, including respiratory problems. By 2 February 1988, the victim showed signs of recovery, but later developed stridor (severe airway obstruction) which was not promptly diagnosed. He died on 15 February 1988. Pathologists testified the death resulted from cardio-respiratory arrest due to complications from treatment of the gunshot wounds. A consultant surgeon argued the death was caused by failure to recognize the airway obstruction. The appellant was convicted of murder. 

Whether the jury should have been directed that negligent medical treatment could break the chain of causation between the shooting and the victim’s death, potentially absolving the defendant of criminal liability. 

The Court of Appeal dismissed the appeal. The jury had been properly directed that the defendant’s acts did not need to be the sole or main cause of death; it was sufficient that the shooting significantly contributed. Negligence in medical treatment does not automatically break the chain of causation unless it is so independent and potent that the defendant’s contribution is rendered insignificant. 

1. In homicide cases, the defendant remains liable if their act is a significant contributing cause of death, even where subsequent medical treatment is negligent.

2. Medical treatment that falls below the expected standard does not necessarily sever the chain of causation. Only acts that are extraordinary, independent, and overwhelmingly potent can do so.

3. Jury directions should focus on whether the defendant’s acts contributed significantly to the death, rather than assessing the degree of fault of medical treatment.