A leading causation authority establishing the “operating and substantial cause” test. Even where negligent or inadequate medical treatment follows an injury, the defendant remains liable unless the subsequent act is so overwhelming that the original wound becomes merely part of the history. This case limits Jordan and is routinely used alongside Blaue to demonstrate the robustness of criminal causation. 

Smith, a private soldier, stabbed a fellow soldier during a barrack-room fight. The victim suffered two stab wounds; one pierced his lung. While being carried for treatment he was twice dropped on the ground, and upon arrival at the medical reception station he received treatment later shown to be wrong and inadequate. There were no blood-transfusion facilities and artificial respiration was applied incorrectly. The victim died roughly two hours after the initial stabbing.

Smith was convicted of murder. He appealed, arguing (1) that confessions made to military officers were wrongly admitted, and (2) that the negligent treatment broke the chain of causation.

Whether the negligent and inappropriate medical treatment, combined with the fact the victim was repeatedly dropped, broke the chain of causation so that the stab wound was not the legal cause of death. 

Appeal dismissed. The stab wound remained an operating and substantial cause of death. The chain of causation was not broken. The conviction stood. 

• The correct test is whether the original wound was still an operating and substantial cause of death at the time the victim died.

• The chain of causation is only broken if the later act is so overwhelming that it renders the original wound merely part of the background.

• The fact that treatment was negligent or poor does not of itself break the chain; it must be “unwarrantable” or “extrinsic” in the sense used in The Oropesa.

• Jordan is exceptional and confined to its facts, where the treatment was “palpably wrong”, in massive doses, and where the original wound had nearly healed.

• Here, despite the dropping of the victim and inadequate treatment, the lung-piercing stab wound continued to cause haemorrhage and was the operative cause of death.