The term is also used to refer collectively to the judges, magistrates and other adjudicators who form the core of a judiciary, as well as the support personnel who keep the system running smoothly. Under the doctrine of the separation of powers, the judiciary is the branch of government primarily responsible for interpreting the law. It construes the laws enacted by the legislature.
It is said that the famed Byzantine Emperor Justinian had the Corpus Juris Civilis compiled and all other decisions by jurists burned to create certainty in the law. Again in the 19th century, French legal scholars at the time of the development of the Code Napoléon advocated the same kind of approach — it was believed that since the law was being written down precisely, it should not need interpretation; and if it did need interpretation, it could be referred to those who wrote the code. Napoleon, who was an advocate of this approach, felt that the task of interpreting the law should be left with the elected legislature, not with unelected judges. This contrasted with the pre-revolutionary situation in France, where unelected 'parliaments' defending the interests of the nobility would often slow the enforcement of royal decisions, including much needed reforms.
However, this idea was found difficult to implement in practice. In France, along with other countries that Napoleon had conquered, or where there was a reception of the Civil Code approach, judges once again assumed an important role, like their English counterparts. In civil law jurisdictions at present, judges interpret the law to about the same extent as in common law jurisdictions – though it may be acknowledged in theory in a different manner than in the common law tradition which directly recognizes the limited power of judges to make law. For instance, in France, the jurisprudence constante of the Cour de cassation or the Conseil d'État is equivalent in practice with case law.
In theory, in the French civil law tradition, a judge does not make new law; he or she merely interprets the intents of "the Legislator." The role of interpretation is traditionally approached more conservatively in civil law jurisdictions than in common law jurisdictions. When the law fails to deal with a situation, doctrinal writers and not judges call for legislative reform, though these legal scholars sometimes influence judicial decisionmaking. So-called "Socialist" law adopted the status of civil law, but added to it a new line of thought derived from Communism — the interpretation of the law is ultimately political, and should serve the purposes of Communism, and hence should not be left to a non-political organ.