English law has depended on the idea that the law is already there, either in longstanding principles of common law or in Acts of Parliament, and the role of the judges is to discover which parts of it are relevant to a particular case.
The principles that they use in doing this then have to be applied in the future in similar cases – the principle known by its Latin name stare decisis – and so a body of judicial precedents are built up over time.
Thus judges are not meant to create the law and are very reluctant to do so, though in practice the way they interpret cases is bound to make changes, especially in response to fundamental changes in society.
At the end of a case the judges, or each judge in the case of appeal decisions as more than one judge decides this, will give a statement, or judgement, on how they reached their decision. This will include:-
a) The facts of the case.
b) The ratio decidendi which is the legal principles that they have applied to the case.
c) The obiter dicta which are other relevant remarks not needed to decide the case but which may provide a view of how the case would be decided if the facts were different.
What the ratio decidendi is may not always be completely clear from the judgement but it is this that forms the precedent that should be applied by the courts in the future.
There are a number of rules on using precedents:-
– The precedents of higher courts are binding on lower courts starting with the European Court of Justice and then the Supreme Court, the Courts of Appeal and then the High Court.
– The European Court of Justice does not recognise the principle of precedent and so may change the principles that it uses from case to case.
– The Supreme Court was not allowed to go against one of its earlier precedents until the Practice Statement by Lord Gardiner, in 1966, that it could where it appears right to do so. It has still been reluctant to use this Statement but, for example, in 1992, the Court overruled the principle that judges could not look at Hansard, which contains the debate in Parliament on new legislation, to interpret what legislation means. Judges can now read what the Minister or MP introducing the legislation says.
– Lower courts cannot go against their own precedents though they can, of course, do so if it conflicts with a precedent used by a higher court or there are two conflicting precedents from previous cases.
– One way in which the various courts can move away from previous precedents is to decide that the facts of the case are somewhat different from the case in which the earlier precedent was set out.
The advantages of judicial precedent is that it is applied uniformly across the courts, the principles of law are reasonably certain, though there is some flexibility, the precedents are related clearly to the facts of the case and there are a wide range of cases to draw on
The disadvantages are that it may be difficult to find the ratio decidendi, case law becomes very complicated and the process can be lengthy.