Cooper v. Aaron
Cooper v. Aaron, 358 U.S. 1 (1958), was a landmark case in which the Little Rock school board tried to stop school desegregation. In deciding this, the Warren Court established the notion of Judicial Supremacy.
In its ruling, the court asserted that the federal judiciary and the U.S. Supreme Court is the "supreme in the exposition of the law of the Constitution" because of one single line that was cited out of context from the Marbury v. Madison opinion. In the opinion of Marbury, Justice Marshall wrote that It is emphatically the province and duty of the Judicial Department to say what the law is. Aaron went far beyond the Court's previous assertion in Marbury however, that they merely had authority to exposit the Constitution. Rather, it asserted the Supreme Court had authority over the other two branches of government, which was unnecessary to the resolution of the dispute in that case.
In setting up the premise for judicial supremacy, the justices committed precedential abuse by asserting that:
This decision declared the basic principle that the federal judiciary is supreme in the exposition of the law of the Constitution, and that principle has ever since been respected by this Court and the Country as a permanent and indispensable feature of our constitutional system.
Unfortunately, Marbury v. Madison makes no such declaration anywhere in its text.