Lawyers argue points of law orally before courts at all levels. The Supreme Court regulates oral argument by court rule. Some cases are decided summarily, without full briefing and argument, on the papers filed by the parties seeking and opposing Supreme Court review. About 150 cases per term are decided with briefs and oral argument. The arguments begin in October, early in the term, and (absent extraordinary circumstances) end in the following April, so that all opinions can be finished by the end of the term.
In the Court's early years oral argument was a leisurely affair; argument in mcculloch v. maryland (1819) lasted nine days. Today, given the increase in the Court's business and increasing doubt that illumination is proportional to talk, argument is normally limited to one-half hour for each side. More time may be allocated to a case that is unusually complicated or important. Permission to argue is only rarely granted to an amicus curiae, except for the solicitor general, who is often allowed to argue orally for the United States as amicus curiae.
The Justices have already read the briefs when they hear counsel. Accordingly, oral argument is no longer a place for oratory. Justices interrupt with their questions and even conduct debates with each other through rhetorical questions to counsel. Time limits on argument are strictly enforced; the red light flashes on the lectern, and counsel stops.
Normally within a few days after oral argument the Justices meet in conference to discuss groups of cases and vote tentatively on their disposition. The Justices regularly say that oral argument, fresh in their minds, influences their thinking in "close" cases. Whether a case is close, however, is a characterization very likely formed before a Justice hears what counsel have to say.
Kenneth L. Karst
Stern, Robert L. and Gressman, Eugene 1978 Supreme Court Practice, 5th ed. Chap. 14. Washington, D.C.: Bureau of National Affairs.