Justice Sonia Sotomayor took the judicial oath on Saturday, becoming the first Hispanic and third woman to serve on the Supreme Court in United States history. At just past 11 a.m., Chief Justice John G. Roberts Jr. administered a pair of oaths to her in two private ceremonies at the Supreme Court building, completing her ascent to a life-tenured position as the nation's 111th justice, and the first to be nominated by a Democratic president since 1994.