Williams v The Bermuda Hospitals Board

A claimant establishes causation by proving on the balance of probabilities that the defendant’s breach caused or materially contributed to the injury. Where wrongful and innocent factors operate cumulatively through a single process, their operation may be concurrent or successive. Their sequence affects the evidence, but creates no legal bar to causation.

This principle does not apply where several disparate factors are merely possible alternative causes and the breach only increased the risk. A tortfeasor who materially contributes to an indivisible injury is liable for the whole injury. Liability for a divisible injury should reflect the attributable share. Evidence of heightened or doubled risk may support an inference, but must not be applied mechanically.

Williams v The Bermuda Hospitals Board concerned a patient who suffered heart and lung injury after a ruptured appendix caused progressively increasing sepsis. The hospital negligently failed to obtain a CT scan on an urgent basis, delaying surgery by at least two hours and 20 minutes.

The trial judge found negligence but held that the patient had not proved that the culpable delay probably caused the complications. He awarded $2,000 for additional pre-operative suffering. The Court of Appeal of Bermuda reversed the causation decision and remitted the claim for reassessment, after which damages were increased to $60,000.

The hospital board appealed to determine whether the Court of Appeal had departed from orthodox causation principles. The central issue was whether the negligent prolongation of a single, progressively worsening septic process materially contributed to the resulting injury, although sepsis had begun before the period of culpable delay.

1. Disposition. Lord Toulson delivered the Board’s judgment. The hospital board’s appeal was dismissed with costs. On the trial judge’s findings, the hospital’s negligence materially contributed to the patient’s heart and lung injury.

2. A claimant must prove on the ordinary civil standard that the breach caused or materially contributed to the injury. Bonnington Castings Ltd v Wardlaw [1956] AC 613 establishes that, where injury results from cumulative operation of innocent and wrongful factors, the relevant question is whether the wrongful factor made a contribution which was more than negligible. A defendant who contributes to an indivisible injury is liable for the whole injury. Where an injury is divisible, liability should reflect the share attributable to the defendant.

3. The cumulative factors need not operate simultaneously. As supported by Hotson v East Berkshire Health Authority [1987] AC 750 and Lord Simon’s reasoning in McGhee v National Coal Board [1973] 1 WLR 1, successive events may each make a material contribution to the outcome. Their sequence remains relevant when deciding whether such a contribution can be inferred on the evidence.

4. The cumulative-cause principle is distinct from a case involving disparate possible causes. Under Wilsher v Essex Area Health Authority [1988] AC 1074, proof that negligence merely added to several risk factors does not establish that it caused the injury. The present case instead involved one known agent, sepsis, operating through a single continuous and progressively worsening process.

5. The trial judge had found that sepsis caused the heart and lung injury and that the septic process continued for at least two hours and 20 minutes longer than it should have done. The greater accumulation increased the heart’s oxygen requirement. It was therefore proper to infer on the balance of probabilities that the negligent delay materially contributed to the process and the resulting injury.

6. Postscript. The Board approved the first-instance result in Bailey v Ministry of Defence [2007] EWHC 2913 (QB), but rejected the Court of Appeal’s characterisation of that case as a departure from the “but-for” test. The total weakened condition had caused the aspiration, while the innocent pancreatitis amounted to a pre-existing vulnerability. The Board also cautioned that a “doubling of risk” analysis must not be applied mechanically. Heightened risk may support an inference of causation, but even a doubled risk may remain very small.

1. Privy Council: Dismissed the hospital board’s appeal with costs. It held that the negligent delay materially contributed to the continuous septic process and resulting injury.

2. Court of Appeal of Bermuda: Reversed the trial judge’s decision on causation and remitted the case for a fresh assessment of damages.

3. Trial court: Hellman J initially found negligence but no proved causation of the complications, awarding $2,000 for additional suffering during the culpable delay. Following remittal, he increased the award to $60,000 excluding interest.