What did the Supreme Court establish in Marbury v. Madison (1803)?

In Marbury v. Madison (1803), the Supreme Court established the principle of judicial review, which is the authority of the courts to review and invalidate government actions that are contrary to the Constitution. This landmark decision, delivered by Chief Justice John Marshall, asserted that it is the duty of the judiciary to interpret the law and ensure that no individual or institution, including Congress, acts beyond its constitutional powers.

The case arose when William Marbury petitioned the Supreme Court for a writ of mandamus to compel Secretary of State James Madison to deliver his commission as a justice of the peace. In ruling against Marbury, the Court declared that the specific provision of the Judiciary Act of 1789 that granted the Supreme Court the power to issue such writs was unconstitutional. This ruling not only denied Marbury his commission but also affirmed the judiciary's role as a check on the other branches of government, thereby establishing judicial review as a fundamental principle of the American legal system.