The rules of causation state that the claimant has to prove that the defendants breach of duty was the factual cause of material damage, when considering the facts of Barnett v Chelsea & Kensington Hospital Management Committee (CKHMC) where the claimants husband became ill after drinking tea which had arsenic, when taken to hospital, the doctor in the casualty department did not examine him and admit him. Instead, he asked the claimant’s husband to see his own GP, a few hours later he passed away.
The casualty doctor owed a duty of care and was in breach of his duty as he did not examine the patient, however, the court held that the doctor should not be liable to pay compensation as there was evidence that even if the doctor had not been negligent and had admitted the claimants husband to hospital he would have died of the arsenic poisoning, thus conveying the fundamental rule of factual causation.
The test widely used to decide the issue of factual causation is the 'but for' test. This is defined by M.A Jones "if harm to the claimant would not have occurred 'but for' the defendants negligence then that negligence is a cause of the harm... If the loss would have incurred in any event, the defendant's conduct is not a cause." When applying the 'but for' test to the Barnett case it is found that as the claimants husband would have died from the arsenic poisoning regardless of the doctor not admitting the patient, the doctors negligence was thus not the cause of the death.
Another case which applied the 'but for test' was Robinson v Post office where a doctor gave his patient a miniscule test dose of an anti-tetanus injection, but instead of waiting for half an hour to see whether the patient was allergic the doctor waited 30 seconds and then administered the full dose. Nine days later the patient