How a Case Reaches the Supreme Court

A few cases begin in the Supreme Court itself under its original jurisdiction, mostly disputes between states over boundaries or water. Nearly all others arrive on appeal from a federal court of appeals or from a state's highest court when the case turns on federal law. Since 1988 almost none must be heard: the losing party files a petition for a writ of certiorari, asking the Court to review the case, and the justices decide whether to grant it. Under the informal rule of four, a case is accepted if four of the nine justices vote to hear it.

The Court receives about 4,000 petitions a year and grants roughly 60, under two percent. Its rules say it looks for cases of national importance, especially conflicts among the federal circuits or state high courts on the same legal question, known as circuit splits, and cases where a lower court has decided an important federal question in a way that conflicts with the Court's precedents. Most justices pool their law clerks to write a shared memo on each petition. The Solicitor General, who represents the federal government, wins review far more often than other petitioners.

Once a case is granted, the parties file written briefs, outside groups file amicus briefs, and the case is argued, usually for an hour, during the term that runs from the first Monday in October. The justices vote in a private conference days later, the senior justice in the majority assigns the opinion, and drafts circulate for months. Decisions in argued cases are typically released by the end of June. The Court also acts on emergency applications, often called the shadow docket or interim docket, deciding urgent requests without full briefing or argument, a practice that has grown sharply in recent years.