In Lambert v Lewis [1982] AC 255, the intervening act was not deemed 'likely to happen' and so broke the chain of causation. In this case, a dealer supplied a defective trailer coupling to a customer who went on using it, after it was obviously broken, until there was an accident. It was held that the dealer was not liable as the accident had been caused by the customer's use of the coupling when he knew that it was broken, and not by the fact that it was defective when sold.