Ratio Decidendi
Where there are multiple possible causes of the claimant's injury, the claimant must prove on the balance of probabilities that the defendant's negligence was a cause. The McGhee material contribution approach does not apply where there are distinct competing causes.
Ffeithiau
A premature baby was given excess oxygen due to a junior doctor's negligence. The baby developed retrolental fibroplasia (blindness), but this condition had five possible causes.
Crynodeb o'r dyfarniad
The House of Lords ordered a retrial. The claimant had to prove that the excess oxygen was a cause of the blindness, not merely that it increased the risk. McGhee did not establish a general principle that increasing risk equated to causation.
Dyfyniadau allweddol
"A plaintiff must prove on the balance of probabilities that the defendant's breach of duty caused or materially contributed to his injury."
— Lord Bridge
Triniaeth ddilynol
Key authority distinguishing material contribution from material increase in risk.