As “a suit at Common Law,” the claim must be tried by the tribunal which has jurisdiction of such suits. But a commissioner can have no such jurisdiction. As “a case arising under the Constitution,” it falls under the judicial power of the United States. But a commissioner is no part of this power. Two provisions of the Constitution place this conclusion beyond question. _First_, by article three, section one, it is declared that “_the judicial power of the United States_ shall be vested in one supreme court, and in such inferior courts as the Congress may from time to time ordain and establish. The judges, both of the supreme and inferior courts, shall hold their offices during good behavior, and shall at stated times receive for their services a compensation which shall not be diminished during their continuance in office.” _Secondly_, by article three, section two, it is declared that “_the judicial power shall extend to all cases in law and equity arising under this Constitution, the laws of the United States_, and treaties made, or which shall be made, under their authority.” Here it appears, first, who are the judges constituting the judicial power of the United States, and, secondly, what is the extent of this power. But a commissioner clearly is not a judge, or any part of the judicial power. Therefore, by inevitable conclusion, he cannot have jurisdiction of any “case arising under the Constitution.” But the Supreme Court has expressly decided that the proceeding by a claimant for the delivery of an alleged slave “constitutes in the strictest sense a controversy between the parties, and _a case arising under the Constitution_ of the United States, within the express delegation of judicial power given by that instrument.”[368]