Bailey v Ministry of Defence [2009] 1 W.L.R. 1052

On 9th January 2001, C was admitted to a hospital managed by D. On 11th January, an operation was carried out to remove C’s gallstone. Following the procedure, C suffered symptoms of pancreatitis. Her treatment proved to be negligent before her transfer to another hospital. As a result of the negligent treatment, C was left unable to clear vomit from her throat. Her choking caused a cardiac arrest, leading C to suffer brain damage. C sued D, arguing that there was a lack of care in C’s resuscitation. Proper care would have led to early intervention and prevented C from becoming as weak as she became. C alleged that this weakness caused, or materially contributed, to her being unable to prevent herself from choking.

Could the negligent care’s material contribution to the claimant’s cumulative weakness establish causation of the resulting brain injury, despite the contribution of her underlying illness?

The Court of Appeal upheld the finding that the negligent care materially contributed to the claimant's weakness and resulting brain injury. Her weakness had cumulative causes: the underlying illness and the consequences of inadequate treatment. That weakness left her unable to protect her airway when she vomited. The relevant finding was a more than negligible contribution to the condition which caused the injury, rather than a mere increase in the statistical possibility of harm. The court accepted material contribution in this cumulative-cause setting. Its reasoning should not be treated as permission to dispense with causal proof whenever medical evidence is uncertain.

Where negligent and non-negligent causes cumulatively produce the condition leading to injury, a proven material contribution to that condition may establish causation. Bailey concerns contribution to actual injury-producing weakness, not a general rule that increasing the risk of injury is sufficient.

Bailey is useful for distinguishing cumulative causes from competing possible causes. Its analysis concerns how negligent care combined with illness to produce weakness, followed by aspiration and brain damage. It belongs alongside Bonnington Castings and the later Privy Council discussion in Williams v Bermuda Hospitals Board. Fairchild addresses a different exceptional risk-based problem. Students should identify the causal mechanism before selecting a test, rather than invoke material contribution whenever ordinary proof appears difficult.