  So one question that can be raised about precedent is why it is justifiable for the decisions of courts to be treated in this way at all, i.e., for them to help constitute the law. There is a more specialised question, however. In the Common Law at least, the doctrine of stare decisis requires later courts to follow earlier decisions even if they were wrongly decided. To say that a case was ‘wrongly decided’ is to say that the legally permissible reasons relevant to the case did not, all things considered, support the conclusion reached by the court. It should be emphasised that such a conclusion depends upon and is relative to the context provided by existing legal doctrine. Take the question of whether parents should be able to recover for the cost of raising a healthy child when it has been born as a result of a negligently performed sterilisation operation on one of the parents. In some legal systems such costs are recoverable, whereas in others they are not. Here it is quite possible that these conflicting decisions are both correct, in the sense that each is correct within its own doctrinal context. So whether a decision is wrong is not a question of how the case ought to be decided without any reference to the law, but whether it goes against the merits of the legally relevant reasons.