In the 19th century, the court's decision in the Dred Scott case led directly to the Civil War.
Many factors contribute to the power of the court, but three are especially crucial. First, the court holds the power to rule that an act of Congress or of the president is unconstitutional. Second, any person who has been adversely affected by a law or an executive act can challenge it as unconstitutional. Third, the Constitution itself contains elastic terms, such as due process of law which allow it to evolve.
Yet, despite the power of the nine unelected justices to make ultimate decisions on vital public issues, it is a curious fact that few members of the public or the press, or even of the legal profession, can name more than one or two, if any, of them. They are appointed by the president and must be confirmed by the Senate. If confirmed, they have life tenure. Because they wield such vast power and are virtually unaccountable, it is vital that they possess not only intellectual and legal qualifications, but also that they reflect the nation's diversity.
Today, seven of the current judges come from the Eastern Seaboard. Six are graduates of Harvard Law School. As for professional background, all nine were on appeals courts before being appointed to the Supreme Court. Despite the fact that women make up half the population and almost half of the legal profession, only one of the nine judges is a woman.