Civil Liability Act 2002

A determination that negligence caused particular harm comprises the following elements—

that the negligence was a necessary condition of the occurrence of the harm (factual causation), and

that it is appropriate for the scope of the negligent person’s liability to extend to the harm so caused (scope of liability).

In determining in an exceptional case, in accordance with established principles, whether negligence that cannot be established as a necessary condition of the occurrence of harm should be accepted as establishing factual causation, the court is to consider (amongst other relevant things) whether or not and why responsibility for the harm should be imposed on the negligent party.

If it is relevant to the determination of factual causation to determine what the person who suffered harm would have done if the negligent person had not been negligent—

the matter is to be determined subjectively in the light of all relevant circumstances, subject to paragraph (b), and

any statement made by the person after suffering the harm about what he or she would have done is inadmissible except to the extent (if any) that the statement is against his or her interest.

For the purpose of determining the scope of liability, the court is to consider (amongst other relevant things) whether or not and why responsibility for the harm should be imposed on the negligent party.