Oral Argument Oral arguments are spoken presentations by lawyers to the Justices of the Supreme Court that highlight the crucial points of a case. The scope of the oral argument cannot exceed the facts established in the trial court record. The purpose of the arguments is to allow the parties to verbalize their viewpoints and give the justices an opportunity to ask questions for further clarification.
Over time the U.S. Supreme Court has altered this procedure slightly. The American system has abandoned strict reliance upon oral presentation in court. The Court has long required the preliminary filing of a written legal brief that explicitly covers all the issues raised. Upon reading the briefs, the justices will decide if the issue is one that warrants oral argument. This decision lies completely within the discretion of the Court and requires the accord of at least four justices. The cases that are normally selected are those that involve interpretations of federal law and/or the U.S. Constitution.
More restrictions were placed on the oral argument procedure as time progressed. Historically, there was no limit either of the number of attorneys who could appear for each side or of the length of time each could argue. However, in 1849 the Supreme Court placed a two-hour restriction on each side's presentation. Total argument time was reduced from two hours per side in 1870 to ninety minutes in 1911 and finally to one half hour in 1984. The Court also limited each side to a single attorney in 1984. However, an attorney may ask the Court for permission to perform a divided argument. Only in this instance will two lawyers be allowed to argue for one side.
(Definition from: Oral Argument. Encyclopedia of the Supreme Court of the United States. Ed. David S. Tanenhaus. Vol. 3. Detroit: Macmillan Reference USA, 2008. p461-463.)