judge-made law
1.Because of the common law tradition, American law comes from four basic sources: the federal and state constitutions, statutes made by the United States Congress and the legislatures of the various states, case law or judge-made law (uncodified law based on judicial decisions), and rules and decisions formulated by administrative agencies collectively known as administrative law.
2.If judges can create laws at will beyond or even discarding the spirits and principles of present laws, authority-exceeding as far as arbitrariness of judicature will occur, which over-magnifies the power of judges with civil rights open to the threats of new judge-made law all the time.
