Mullin v Richards [1998] 1 All ER 920 is a judgment of the Court of Appeal of England and Wales, dealing with liability of children under English law of negligence.
[1] The question in the case was what standard of behaviour could be expected of a child.
The plaintiff and the defendant, two female friends of fifteen years old, were fencing with plastic rulers in their classroom.
One of the rulers shattered and a piece of plastic flew into the plaintiff girl's eye, partially depriving her of sight.
It was held that an ordinary prudent 15-year old could not have foreseen any injury when playing with rulers and the defendant was therefore found not liable in negligence.