The Roberts Court refers to the Supreme Court of the United States since 2005, under the leadership of Chief Justice John G. Roberts. It is generally considered more conservative than the preceding Rehnquist Court, as a result of the retirement of moderate Justice Sandra Day O'Connor and the subsequent confirmation of the more conservative Justice Samuel Alito in her place.
Roberts was originally nominated by President George W. Bush to replace Associate Justice Sandra Day O'Connor, who had decided to retire from the Court, effective with the confirmation of her successor. However, before the Senate could act upon Roberts' nomination to be an Associate Justice, Chief Justice William Rehnquist died, and President Bush nominated Roberts for the Chief Justice vacancy. Roberts' nomination as Chief Justice was confirmed by the Senate in 2005. Roberts took the Constitutional oath of office, administered by senior Associate Justice John Paul Stevens at the White House, on September 29, 2005, almost immediately after his confirmation. On October 3, Roberts took the judicial oath provided for by the Judiciary Act of 1789, prior to the first oral arguments of the 2005 term. The Roberts Court commenced with Roberts as Chief Justice and eight holdovers from the Rehnquist Court: Stevens, O'Connor, Antonin Scalia, Anthony Kennedy, David Souter, Clarence Thomas, Ruth Bader Ginsburg, and Stephen Breyer.