The best way to grasp the distinction between administrative and judicial decisions is to look at both in action. In the judicial process we have the judge, who is a known person and not associated with any party to the proceedings. The evidence tendered to the court is available to all parties, and there are opportunities for testing and criticising evidence tendered by an opposing party; parties may be legally represented and put forward arguments on facts or on law. The judge is expected to base his decision on law and to explain what he has done by ‘giving reasons’. The assumption is that some law must be applicable and that this law is ascertainable by a process of considering principles that can be found in books of authority. The judge often has to exercise a discretion, but he will generally find that there is some precedent and that he cannot do just whatever he thinks would be best. There are times when a judge does have such a wide choice that it is proper to say he can decide on the ground of what he thinks is the best policy, but that is regarded as the result of there being gaps in the law; he may have to make policy decisions, but that is not his real business.