At both the federal and state level, there are three equal but distinct branches of government:
Federal and state courts are part of the judicial branch of government.
Separation of Powers
The framers of the Constitution created three equal branches to prevent any one branch from having too much power. Our country's system of government rests on a separation of powers. The legislative branch -- Congress at the federal level and legislatures at the state level -- makes the laws. Executive branch departments execute and enforce the laws -- the President at the federal level and governors at the state level. It is the job of the judicial branch to apply and interpret the laws and to resolve disputes that arise under them. No branch may perform functions reserved for the other branches. Federal and state courts may exercise only judicial powers and perform only judicial functions, and judges can decide only cases that are before them.
The Judicial Branch in Operation
The judicial branches of the federal and state governments operate within their respective court systems. A court is an institution that the government sets up to settle disputes through a legal process. People come to court to resolve their disagreements. Courts decide what really happened and what should be done about it. They decide whether a person committed a crime and what the punishment should be. They also provide a peaceful way to decide private disputes that people can't resolve themselves.