<P> The U.S. federal court system hears cases involving litigants from two or more states , violations of federal laws , treaties , and the Constitution , admiralty , bankruptcy , and related issues . In practice , about 80 % of the cases are civil and 20 % criminal . The civil cases often involve civil rights , patents , and Social Security while the criminal cases involve tax fraud , robbery , counterfeiting , and drug crimes . The trial courts are U.S. district courts , followed by United States courts of appeals and then the Supreme Court of the United States . The judicial system , whether state or federal , begins with a court of first instance , whose work may be reviewed by an appellate court , and then ends at the court of last resort , which may review the work of the lower courts . </P>
what is the highest court in the federal court system
Supreme Court of the United States