The First Congress passed the Judiciary Act of 1789, the law that created the U.S. Supreme Court and the lower federal court system. The act allowed for six Supreme Court justices. This number fluctuated until it was fixed at nine after the Civil War. The Judiciary Act of 1789 also expanded the authority and responsibilities of the Supreme Court beyond what is described in the Constitution. This increased authority included the power of the Court to issue a writ of mandamus, or a formal order to a government official to fulfill the duties of the official's office. The act's allowance of writs of mandamus resulted in the judiciary claiming one of its most important powers: the power of judicial review. Judicial review is the right of a court to review the laws and actions of the other two branches. Marbury v. Madison was the 1803 Supreme Court ruling that established the principle of judicial review.
In 1801 outgoing president John Adams appointed a number of new federal judges. Adams nominated candidates who were, like him, Federalists, hoping to protect Federalist influence under incoming president Thomas Jefferson, a Democratic-Republican. The Senate confirmed the appointments. However, not all of the commissions, or formal assignments, were delivered to the new judges by the time Jefferson assumed the presidency. Intending to fill the posts with friendlier judges, Jefferson directed his secretary of state, James Madison, not to deliver the remaining commissions. William Marbury, one of the individuals who did not receive his commission, petitioned the Supreme Court to issue a writ of mandamus forcing Madison to deliver the commission.
John Marshall, chief justice of the U.S. Supreme Court (1801–35), realized the case presented a problem of authority for the court. If the court issued the writ of mandamus, Madison was unlikely to obey it. Unable to enforce its ruling in any way, the court would look ineffectual. However, if the court did not issue the writ, it would appear that the justices were simply deferring to the executive branch, making it look weak.
In his ruling, Marshall avoided these undesirable outcomes by approaching the case from another angle: constitutionality. Marshall and a unanimous court declared that the court actually had no right to issue a writ because the section of the Judiciary Act that authorized a writ of mandamus was unconstitutional. The court then dismissed Marbury's case on the grounds of lack of jurisdiction, or a court's authority to hear and decide a case. Importantly, Marshall's ruling included this statement:
It is also not entirely unworthy of observation that, in declaring what shall be the supreme law of the land, the Constitution itself is first mentioned; and not the laws of the United States generally, but those only which shall be made in pursuance of the Constitution, have that rank. Thus, the particular phraseology of the constitution of the United States confirms and strengthens the principle, supposed to be essential to all written constitutions, that a law repugnant to the constitution is void; and that courts, as well as other departments, are bound by that instrument.