In 2003, Roberts was appointed as a judge of the United States Court of Appeals for the District of Columbia Circuit by George W. Bush. During his two-year tenure on the D.C. Circuit, Roberts authored 49 opinions, eliciting two dissents from other judges, and authoring three dissents of his own. In 2005, Roberts was nominated to be an associate justice of the Supreme Court, initially to succeed the retiring Sandra Day O'Connor. When Rehnquist died before Roberts's confirmation hearings began, Bush instead nominated Roberts to fill the chief justice position.