_The District Courts._--The lowest grade of federal court is the district court, held in each of the districts (about eighty) into which the country is divided. In some cases a state constitutes one district; in other cases a state is divided into two, three, four, or five districts. Usually there is one judge for each district, though in a few cases there are several judges for a single district, each holding court separately. The jurisdiction of the district court embraces civil and criminal cases under the laws of the United States--such as suits for the infringement of patents and copyrights, admiralty cases, bankruptcy proceedings, revenue cases; and offenses against the United States revenue laws, laws against counterfeiting, the public land laws, the pure food laws, the postal laws, and the interstate commerce laws. Controversies between citizens of different states may also be brought to this court.[99] [99] Such suits may also be brought in the state courts but may at the option of the defendant be transferred to a federal court for trial. Many lawyers prefer to bring their suits in the state courts even when they have the privilege of suing in the federal courts, because of their greater familiarity with the procedure of these courts. In most cases appeals may be taken from the decisions of the district courts to the circuit courts of appeals or to the Supreme Court. =Federal Attorneys, Marshals, and Clerks.=--In each of the federal judicial districts, there is a United States attorney who prosecutes violations of the federal laws in his district. There is also in each district a United States marshal who bears somewhat the same relation to the federal court that a sheriff does to a state court. He executes the processes of the court, arrests offenders, and performs other ministerial functions for the court. In each district there is a clerk who has custody of the seal of the court and keeps a record of its proceedings, orders, judgments, etc. The marshal and attorney are appointed by the President, but the clerk is chosen by the court itself. In each district, also, the court appoints a number of United States commissioners who are empowered to issue warrants for arrest, take bail, determine whether accused persons shall be held for trial, and perform other duties somewhat similar to those discharged by justices of the peace under the judicial system of the state. =The Regular Federal Judges.=--_Appointment._--All federal judges are appointed by the President, by and with the advice and consent of the Senate. The judges of most of the states, as we have seen, are now chosen by popular election, but that method did not commend itself to the framers of the federal Constitution. The existing method of appointing federal judges has given general satisfaction, and with remarkably few exceptions, the persons appointed to the federal bench have been men of integrity and fitness.[100]