The Hierarchy of Courts is represented by this Hierarchy of Legal Authority chart. The courts are divided into three levels: trial, appellate, and court of last resort. The term trial is self-explanatory; it is the basic level the action is initiated. The Supreme Court of the United States is the highest court in the land and the only part of the federal judiciary that the Constitution requires. The number of Supreme Court Justices is determined by Congress rather than the Constitution. This Hierarchy of legal authority chart also depicts the basic structure of the United States court systems and the Hierarchy of their jurisdiction, which is an important skill for any legal researcher.