Barkway v South Wales Transport [1950] AC 185



The claimant was injured when a bus drove off the road because of a latent, undetectable defect in the tyre that made it burst. There was evidence that the bus company ought to have made drivers report impacts which could cause this sort of defect, and had not done so. The claimant sued the defendant bus company in the tort of negligence.


To prove negligence, the claimant must show that the defendant breached their duty of care: that the defendant failed to act as a reasonable person would in their position.

Where it is not possible for the claimant to prove exactly what the accident’s cause was, the court will presume breach if the defendant was in control of the situation and the accident was not one which normally occurs without carelessness. This is the doctrine of res ipsa loquitur.

The issue in this case was what the doctrine means when it requires the cause of the accident to be unknown.


The House of Lords held that this was not a case where the doctrine of res ipsa loquitur applied.

The House of Lords held that doctrine required the cause of the accident to be completely unknown. It was not applicable in a case where all the facts relating to the accident are known and the judge is merely being asked to decide between two or more competing interpretations of events.

In this case, all the relevant facts as to how the accident arose were known, and the judge was merely asked to decide whether the defendant’s reporting policies were negligent and could have prevented the harm. As such, the claimant retained the burden of proving negligence as usual.