Section 13 of the Judiciary Act of 1789 is unconstitutional because it attempts to expand the original jurisdiction of the Supreme Court beyond that permitted by the Constitution. Congress cannot pass laws that contradict the Constitution. This case featured the first example of judicial nullification of a federal law and it was the point at which the Supreme Court adopted a monitoring role over government actions. Decided February 24, 1803 (argued February 11, 1803). Opinion of the Court: John Marshall → go there Topic: Separation of powers. Marbury v. Madison, 5 U.S. 137 (1803), is a landmark decision of the Supreme Court of the United States that established the principle of judicial review, meaning that American courts have the power to strike down laws and statutes they find to violate the Constitution of the United States. Decided in 1803, Marbury is regarded as the single most important decision in American constitutional law. It established that the U.S. Constitution is actually law, not merely a statement of political principles and ideals. It also helped define the boundary between the constitutionally separate executive and judicial branches of the federal government. Wiki link