Elena Kagan Sworn In

Elena Kagan was sworn in Saturday morning as the 112th justice to serve on the Supreme Court.

The former dean of Harvard Law School took two required oaths from Chief Justice John Roberts, promising in her second oath to "do equal right to the poor and to the rich." She succeeds Justice John Paul Stevens.

Kagan was confirmed to the Supreme Court on Thursday with the backing of nearly all Democrats, two independents, and a few Republicans in the Senate.

She is the fourth woman ever to serve on the Supreme Court and joins justices Ginsburg and Sotomayor to mark the first time three women have served at the same time.

During her confirmation hearings, some Republican senators criticized Kagan, a former dean of Harvard Law School, for her decision to limit assistance to military recruiters on campus because of the "don't ask, don't tell" policy, which she has denounced. They also questioned why, as solicitor general, she did not pursue a legal challenge to the policy.

One of the cases the high court may hear in the coming years is the one involving California's Proposition 8. Proponents of the anti-marriage equality measure are seeking to appeal federal judge Vaughn Walker's Wednesday ruling striking it down.

A formal investiture will take place October 1, three days before the justices begin their next term.