The US Federal Court System is divided in 4: The Federal Trial Courts, The Federal Appeals Courts, The US Supreme Court and The Independence of the Federal Judiciary. In the first one the trial courts are called the US districts courts which hace juridiction over cases that involve the intepretation of federal statutes. The second one, related to the 94 federal judicial districts, fall into 12 regional circuits, ot hears appeals from all district courts and the decisions of federal administrative agencies too. The third one consists of the chief justice and the cases they took are appealed from state or federal courts. The last one, promotes judicial independence by appointing the judges for life and without reducing their salary.