The U.S. Constitution created a governmental structure for the United States known as federalism. Federalism refers to a sharing of powers between the national government and the state governments. The Constitution gives certain powers to the federal government and reserves the rest for the states. Therefore, while the Constitution states that the federal government is supreme with regard to those powers expressly or implicitly delegated to it, the states remain supreme in matters reserved to them. This supremacy of each government in its own sphere is known as separate sovereignty, meaning each government is sovereign in its own right.
Both the federal and state governments need their own court systems to apply and interpret their laws. Furthermore, both the federal and state constitutions attempt to do this by specifically spelling out the jurisdiction of their respective court systems.
For example, since the Constitution gives Congress sole authority to make uniform laws concerning bankruptcies, a state court would lack jurisdiction in this matter. Likewise, since the Constitution does not give the federal government authority in most matters concerning the regulation of the family, a federal court would lack jurisdiction in a divorce case. This is why there are two separate court systems in America. The federal court system deals with issues of law relating to those powers expressly or implicitly granted to it by the U.S. Constitution, while the state court systems deal with issues of law relating to those matters that the U.S. Constitution did not give to the federal government or explicitly relay to the states.
