Judicial decision is not only an application of law but contains law making by the judge. It is well-known since the american legal realism and the german free law movement found out it.
When we recognize it as a fact and furthermore use law making by the judge as an instrument for law making in order to settle the new coming problems in society, we should analyze the process of law making by the judge and try to adjust it to the principle of the separation of power between judicatory and legislative. Because law making should not be the task of the judge but belong to power of legislative.
In this paper we discuss the problem how we can control law making by the judge in order to prevent an arbitrary judgement and the methodology on judicial decision that controls the process of law making by the judge. In japanese and german context law making against statutory law can be permitted exceptionally. According to the methodology law making against statutory law (houritsu. Gesetz) must be made within the higher law order (ho. Recht). What is the higher law order? Sociology of law should research into this problem in collaboration with methodological jurisprudence.
