Cooper v. Aaron, 358 U.S. 1 (1958), is a landmark United States Supreme Court decision arising from the Little Rock, Arkansas school desegregation crisis. After the Court's ruling in Brown v. Board of Education (1954) declared racial segregation in public schools unconstitutional under the Equal Protection Clause of the Fourteenth Amendment, the Little Rock school board adopted a gradual integration plan. Arkansas Governor Orval Faubus deployed the National Guard to block nine Black students (the "Little Rock Nine") from entering Central High School in September 1957, prompting President Dwight D. Eisenhower to federalize the Guard and dispatch the 101st Airborne Division to enforce the order. The school board subsequently petitioned to suspend its desegregation plan for two and a half years, citing the public hostility and disorder; the case reached the Supreme Court on review of that request.
The Court unanimously rejected the delay, holding that the constitutional rights of the children "are not to be sacrificed or yielded to the violence and disorder" engineered by state officials. The opinion's enduring significance lies in its forceful articulation of judicial supremacy: it declared that Marbury v. Madison (1803) established the federal judiciary as "supreme in the exposition of the law of the Constitution," and that this principle "has ever since been respected by this Court and the Country as a permanent and indispensable feature of our constitutional system." The interpretation of the Fourteenth Amendment in Brown was therefore "the supreme law of the land," binding on state officials under Article VI's Supremacy Clause and the oath every legislator and executive officer swears to support the Constitution. State authorities could not nullify a federal constitutional ruling "openly and directly" or "by evasive schemes."
A distinctive feature of Cooper v. Aaron is that all nine Justices individually signed the opinion — an unprecedented gesture underscoring the Court's collective resolve against the doctrines of "interposition" and "nullification" then being revived across the segregationist South in resistance to Brown. The decision rejected the argument that the Governor and legislature of a state were not bound by Brown because they had not been parties to that litigation. Its reasoning has since anchored the modern understanding that the Supreme Court's constitutional interpretations bind coordinate branches and the states alike, a position later invoked in debates over "departmentalism" and decisions such as United States v. Nixon (1974) and City of Boerne v. Flores (1997).
For the FSOT (U.S. Government) and comparative constitutional law sections, Cooper v. Aaron is tested on two angles: first, as a pillar of judicial supremacy and the binding force of Brown, often paired with Marbury and the Supremacy Clause; second, as the legal climax of the Little Rock crisis, illustrating federal-state confrontation over civil rights enforcement and the President's power to enforce court orders. Candidates should be able to distinguish judicial review (Marbury) from judicial supremacy (Cooper) and explain why the unanimous, individually-signed opinion mattered politically.
Example
In September 1957, President Dwight D. Eisenhower federalized the Arkansas National Guard and sent the 101st Airborne to escort the Little Rock Nine into Central High School, the confrontation that produced Cooper v. Aaron in 1958.
Frequently asked questions
It establishes judicial supremacy — that the Supreme Court's interpretation of the Constitution is the supreme law of the land and binds state officials under the Supremacy Clause of Article VI. States cannot nullify or evade federal constitutional rulings such as Brown v. Board of Education.