Marbury v. Madison
5 U.S. 137 (1803), declared, for the first time, an act of Congress unconstitutional, thus establishing the doctrine of judicial review. The Supreme Court held that a section of the Judiciary Act of 1789 (specifically, Section 13, which authorized the Court to issue a writ of mandamus) was unconstitutional and thus invalid. Chief Justice John Marshall declared that in any conflict between the Constitution and a law passed by Congress, the Constitution must always take precedence.
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