what is the rule of four

The Rule of Four is a custom of the United States Supreme Court that dictates that if four justices decide that a case is worthy of being heard, the Court will agree to hear it. This rule is designed to prevent a majority of the Courts members from controlling their docket. The rule is not required by the US Constitution, any law, or even the Courts own published rules. Rather, it is a custom that has been observed since the Court was given discretion on hearing appeals by the Judiciary Act of 1891, Judiciary Act of 1925, and the Supreme Court Case Selections Act of 1988. Before granting a writ of certiorari, the justices must vote to decide whether or not the case has merit. In many instances, five of the Supreme Court justices dominate the court on particular issues, so the rule of four ensures that the four judges who often vote in the minority still get a say in what happens at the court, preventing an imbalance of power that could be created by the majority of justices. The rule of four is not dictated by any law or the Constitution, and it is an unwritten internal rule of the Supreme Court.