Sandra Day O'Connor was an American attorney, politician, and jurist who served as an associate justice of the Supreme Court of the United States from 1981 to 2006. O'Connor was the first woman to serve as a U.S. Supreme Court justice. She was a moderate conservative. Nominated by President Ronald Reagan, she was considered a swing vote for the Rehnquist Court and the first four months of the Roberts Court. Before O'Connor's tenure on the Court, she was an Arizona state judge and earlier an elected legislator in Arizona, serving as the first female majority leader of a state senate as the Republican leader in the Arizona Senate. Upon her nomination to the Court, O'Connor was confirmed unanimously by the United States Senate.

The Rehnquist Court was the period in the history of the Supreme Court of the United States during which William Rehnquist served as Chief Justice. Rehnquist succeeded Warren Burger as Chief Justice after the latter's retirement, and Rehnquist held this position until his death in 2005, at which point John Roberts was nominated and confirmed as Rehnquist's replacement. The Rehnquist Court is generally considered to be more conservative than the preceding Burger Court, but not as conservative as the succeeding Roberts Court. According to Jeffrey Rosen, Rehnquist combined an amiable nature with great organizational skill, and he "led a Court that put the brakes on some of the excesses of the Earl Warren era while keeping pace with the sentiments of a majority of the country."