The jurisdiction of the federal courts is defined in Article III, Section 2, of the Constitution, as extending in law and equity to all cases arising under the Constitution and federal legislation; to controversies to which the U. S. shall be a party, including those arising from treaties with other governments; to admiralty and maritime cases; to controversies between states; to controversies between a state, or its citizens, and foreign governments or their subjects; and to controversies between the citizens of one state and citizens of another state. The federal courts were also originally invested with jurisdiction over controversies between citizens of one state and the government of another state; the 11 th Amendment (ratified February 7, 1795), however, removed from federal jurisdiction those cases in which the citizens of one state were plaintiffs and the government of another state was the defendant.

The amendment did not disturb the jurisdiction of the federal courts in cases in which a state government is a plaintiff and a citizen of another state, the defendant. Federal courts have exclusive jurisdiction in patent and copyright cases; and by congressional enactment in 1898, federal courts were vested with original jurisdiction in bankruptcy cases. The courts established under the powers granted by Article III, Sections 1 and 2, of the Constitution are known as constitutional courts. Judges of constitutional courts are appointed for life by the president with the approval of the Senate.

These courts are the district courts, tribunals of general original jurisdiction; the courts of appeals (before 1948, circuit courts of appeals), exercising appellate jurisdiction over the district courts; and the Supreme Court. A district court functions in each of the more than 90 federal judicial districts and in the District of Columbia. A court of appeals functions in each of the 11 federal judicial circuits and in the District of Columbia; there is also a more specialized court with nationwide jurisdiction known as the court of appeals for the federal circuit. The federal district court and the court of appeals of the District of Columbia perform functions discharged in the states by state courts. All lower federal courts operate under uniform rules of procedure promulgated by the Supreme Court. The Supreme Court is the highest appellate tribunal in the country and is a court of original jurisdiction according to the Constitution "in all cases affecting Ambassadors, other public ministers and Consuls, and those in which a State shall be a Party." By virtue of its power of review, the Supreme Court is also the final judicial arbiter of federal constitutional questions and of the scope of federal statutes.

Other federal courts, established by Congress under powers held to be implied in other articles of the Constitution, are called legislative courts. These are the Claims Court, the Court of International Trade, the Tax Court, and the territorial courts established in the federally administered territories of the U. S. The special jurisdictions of these courts are defined by the U.

S. Congress. Except in the case of the territorial courts, which are courts of general jurisdiction, the special jurisdictions of these courts are suggested by their titles. State Courts Each state has an independent system of courts operating under the constitution and laws of the state. Broadly speaking, the state courts are based on the English judicial system as it existed in colonial times, but as modified by statutory enactment's; the character and names of the courts differ from state to state. The state courts as a whole have general jurisdiction, except in cases in which exclusive jurisdiction has been vested in the federal courts.

In cases involving the federal Constitution or federal laws or treaties, the state courts are governed by the decisions of the Supreme Court and their decisions are subject to review by that Court. Cases involving the federal Constitution, federal laws, or treaties may be brought to either the state courts or the federal courts. Ordinary civil suits not involving any of those elements can be brought only to the state courts, except in cases of diversity of citizenship between the parties, in which event the suit may be brought to a federal court. By act of Congress, however, suits involving federal questions or diversity of citizenship may be brought to the federal courts only when the controversy involves $10, 000 or more, so that all such cases involving a smaller amount must be brought to the state courts exclusively. In accordance with a congressional enactment, a suit brought to a state court that could have been brought to a federal court may be removed to the federal court at the option of the defendant.

Bearing in mind that any statement about state courts purporting to give a typical description of them is subject to numerous exceptions, the following information may be taken as general comprehensive statements of their jurisdictions and organization. County courts of general original jurisdiction exercise both law and equity jurisdictions in most of the states; a few states maintain the system of separate courts of law and equity inherited from the English judicial system. Most states also maintain separate criminal and civil courts of original jurisdiction. In some states, the same courts of original jurisdiction deal with both civil and criminal cases; these courts usually have two levels, one handling misdemeanors and civil claims under $5000, the other handling felonies and civil claims over $5000. Between the lower courts and the supreme appellate courts, in a number of states, are intermediate appellate courts which, like the federal courts of appeals, provide speedier justice for litigants by disposing of a large number of cases that otherwise would be added to the overcrowded calendars of the higher courts. Courts of last resort, the highest appellate tribunals of the states in criminal and civil cases and in law and equity, are generally called supreme courts.

In New York state, however, the Supreme Court is a trial court; the highest appellate court of New York, as well as of Maryland, is called the Court of Appeals. The state court systems also include a number of minor courts with limited jurisdiction. These courts dispose of minor offenses and relatively small civil actions. Included in this classification are police and municipal courts in cities and larger towns and the courts presided over by justices of the peace in rural areas.