What case did John Marshall uphold the constitutionality of the national bank?
McCulloch v. Maryland, (1819)
Key decisions of the Supreme Court under the leadership of John Marshall solidified the power of the Supreme Court to?
Chief Justice John Marshall is credited with affirming the doctrine of judicial review by declaring Section 13 of the Judiciary Act of 1789 unconstitutional in Marbury v. Madison, 5 US 137 (1803). Although the Supreme Court under John Marshall was not the first to review a law for constitutionality, he was the first to declare an act of Congress unconstitutional. For more information, see Related Questions, below.
Marshall believed the Judicial Branch should be co-equal to the other branches of government, and should be the final authority on constitutional interpretation. He knew Congress couldn't be counted on to evaluate the constitutionality of their own laws because of the built-in conflict-of-interest, and believed this was the proper job of the judiciary.