The tort of negligence does not impose liability whenever someone fails to take reasonable care. The claimant must show that the the defendant is ‘responsible’ for their loss, primarily by showing that the defendant owed them a ‘duty of care’.
The ‘duty of care’ cases ask two different questions: firstly, whether the context is appropriate for the tort of negligence; and secondly whether in fact there was a duty owed. The former can be called the notional duty. The law defines certain rules which determine as a matter of law whether a ‘duty’ could be owed. In this sense, the duty acts as a control mechanism for the tort of negligence. The second question asks whether a duty is in fact owed and involves an application of the defined rules or tests.
It is easier to understand the duty of care cases by distinguishing when the Court is discussing the notional duty and the factual duty. In some cases, the Judges seek to answer both of these questions during their judgement.
The first set of cases consider the theory of the ‘duty of care’ and attempt to identify a principles test. The following sets of cases each look at how the test or tests are applied in specific, troublesome contexts.