Supreme Court 101: How it works and what's at stake now

Ray Sanchez, CNN | 1/31/2017, 4:03 p.m.
The nation will be watching closely when President Donald Trump reveals his nominee for the Supreme Court Tuesday night.
Supreme Court Richard Jenrette/CNN

Ginsburg, who will turn 84 in March, is the court's eldest justice. Breyer will turn 79 in August.

What is the primary purpose of the court?

The justices serve as the final word for a nation built on the rule of law.

They interpret the Constitution, which involves every aspect of our lives -- how we conduct ourselves in society and boundaries for individuals and the government.

As the late justice William Brennan once wrote, "The law is not an end in itself, nor does it provide ends. It is preeminently a means to serve what we think is right."

When it came to deciding who won the 2000 presidential election, for instance, the conclusions of the Supreme Court ultimately resolved the issue, even though the controversy lingers.

Why was the Supreme Court created?

The first meeting of the Supreme Court was in 1790.

The court is led by the Chief Justice of the United States (that's the official title). All justices -- and all federal judges -- are first nominated by the president and must be confirmed by the Senate. They serve for as long as they choose.

The court has occupied its current building in Washington only since 1935. Previously, it borrowed space in Senate chambers in the Capitol Building.

The Constitution's framers envisioned the judiciary as the "weakest," "least dangerous" branch of government.

Over the years, the court has often been accused of being too timid in asserting its power. But when the justices flex their judicial muscle, the results can be far-reaching.

Consider cases such as Brown v. Board of Education (1954 -- integrated public schools), Roe v. Wade (1973 -- legalized abortion) and even Bush v. Gore (2000 -- resolved the disputed presidential election).

How does the court work?

Traditionally, each Supreme Court term begins the first Monday in October, and final opinions are issued usually by late June.

The justices divide their time between "sittings," where they hear cases and issue decisions, and "recesses," where they meet in private to write their decisions and consider other business before the court.

Court arguments are open to the public in the main courtroom, and visitors have the option of watching all the arguments or only a small portion.

Traditions are observed. The justices wear black robes. Quill pins still adorn the desks, as they have for more than two centuries.

The justices are seated by seniority, with the chief justice in the middle. The two junior justices (currently Sotomayor and Kagan) occupy the opposite ends of the bench.

Before public arguments and private conferences, where decisions are discussed, the nine members all shake hands as a show of harmony of purpose.

Arguments usually begin at 10 a.m. and since most cases involve appellate review of decisions by other courts, there are no juries or witnesses, just lawyers from both sides addressing the bench. The cases usually last about an hour. Lawyers from both sides very often have their prepared oral briefs interrupted by pointed questions from a justice.

How many cases are accepted?

Each week, the court receives more than 150 petitions for review -- decisions by lower courts appealed to the high court. Relatively few are granted full review. About 8,000 to 10,000 such petitions go on the court's docket each term.

Only 75 to 85 cases -- about 1% -- are accepted.

Court opinions are final. The only exception is the court itself, which can over time overturn its own precedent, as it did with racial segregation. But most justices rely on the principle of "stare decisis," Latin for "to stand by a decision," where a current court should be bound by previous rulings.

CNN's Bill Mears and Joan Biskupic contributed to this report.