Elena Kagan Sworn in as 4th Woman in History on Supreme Court

She smiled broadly as admirers stood and applauded. New Yorker Elena Kagan was sworn in Saturday as the Supreme Court's 112th justice, the third woman on the current bench and the fourth female ever to serve on the highest court in the land.

Kagan, 50, has never before been a judge at any level, but she has appeared before the Supreme Court as the nation's solicitor general and before that was dean of the Harvard Law School and a counsel to the Clinton White House.

Chief Justice John Roberts administered two oaths: one in a ceremony in a conference room at the court with only her family present, and then a second with friends and reporters in attendance, the Associated Press said. "We look forward to serving with you," Roberts told her.

Kagan was confirmed by the Senate 63-37 on Thursday. Republicans complained about her lack of judicial experience and liberal leanings.

She won't be formally installed until the new court term begins on Oct. 1, but she can assume the duties of a justice, including reviewing cases and emergency appeals. Going in, Kagan won't change the balance of the court, which often splits 5-4 with a conservative edge on politically-charged cases. She joins Justices Ruth Bader Ginsburg and Sonia Sotomayor in the womens' caucus; the first female justice, Sandra Day O'Connor, retired in 2005.