Obergefell v. Hodges, 576 U.S. 644 (2015), is a landmark decision of the Supreme Court of the United States which ruled that the fundamental right to marry is guaranteed to same-sex couples by both the Due Process Clause and the Equal Protection Clause of the Fourteenth Amendment of the Constitution. The 5–4 ruling requires all fifty states, the District of Columbia, and the Insular Areas to perform and recognize the marriages of same-sex couples on the same terms and conditions as the marriages of opposite-sex couples, with all the accompanying rights and responsibilities. Prior to Obergefell, same-sex marriage had already been established by statute, court ruling, or voter initiative in thirty-six states, the District of Columbia, and Guam.

The Supreme Court of the United States (SCOTUS) is the highest court in the federal judiciary of the United States. It has ultimate appellate jurisdiction over all U.S. federal court cases, and over state court cases that turn on questions of U.S. constitutional or federal law. It also has original jurisdiction over a narrow range of cases, specifically "all Cases affecting Ambassadors, other public Ministers and Consuls, and those in which a State shall be Party." The court holds the power of judicial review: the ability to invalidate a statute for violating a provision of the Constitution. It is also able to strike down presidential directives for violating either the Constitution or statutory law.