<P> Article III authorizes one Supreme Court, but does not set the number of justices that must be appointed to it . Article I, Section 3, Clause 6 refers to a Chief Justice (who shall preside over the impeachment trial of a President). The number of justices is fixed by statute at nine: the one chief justice, and eight associate justices . </P> <P> Proposals to divide the Supreme Court into separate panels have been made, but all have failed . Because all such proposals have failed, the Supreme Court has never ruled on the constitutionality of such a division . Chief Justice Charles Evans Hughes wrote, "the Constitution does not appear to authorize two or more Supreme Courts functioning in effect as separate courts ." </P> <P> The Supreme Court is the only federal court that is explicitly mandated by the Constitution . During the Constitutional Convention, a proposal was made for the Supreme Court to be the only federal court, having both original jurisdiction and appellate jurisdiction . This proposal was rejected in favor of the provision that exists today . Under this provision, the Congress may create inferior (i.e., lower) courts under both Article III, Section 1, and Article I, Section 8 . The Article III courts, which are also known as "constitutional courts", were first created by the Judiciary Act of 1789 . Article I courts, which are also known as "legislative courts", consist of regulatory agencies, such as the United States Tax Court . Article III courts are the only ones with judicial power, and so decisions of regulatory agencies remain subject to review by Article III courts . However, cases not requiring "judicial determination" may come before Article I courts . In the case of ((Murray's Lessee v. Hoboken Land & Improvement Co .)) 59 U.S. 272 (1855), the Supreme Court ruled that cases involving "a suit at the common law, or in equity, or admiralty" inherently involve judicial determination and must come before Article III courts . Other cases, such as bankruptcy cases, have been held not to involve judicial determination, and may therefore go before Article I courts . Similarly, several courts in the District of Columbia, which is under the exclusive jurisdiction of the Congress, are Article I courts rather than Article III courts . This article was expressly extended to the United States District Court for the District of Puerto Rico by the U.S. Congress through Federal Law 89 - 571, 80 Stat. 764, signed by President Lyndon B. Johnson in 1966 . This transformed the article IV United States territorial court in Puerto Rico, created in 1900, to an Article III federal judicial district court . </P> <P> The Judicial Procedures Reform Bill of 1937--frequently called the court - packing plan,--was a legislative initiative to add more justices to the Supreme Court proposed by U.S. President Franklin Roosevelt shortly after his victory in the 1936 presidential election . Although the bill aimed generally to overhaul and modernize all of the federal court system, its central and most controversial provision would have granted the President power to appoint an additional Justice to the U.S. Supreme Court for every sitting member over the age of 701⁄2, up to a maximum of six . </P>

The only type of court(s) required by the constitution is/are