Sotomayor sworn in as Supreme Court justice

updated 7:32 p.m. ET Aug. 8, 2009

WASHINGTON - Sonia Sotomayor was sworn in Saturday as the Supreme Court's first Hispanic justice and only third female member in the top U.S. court's 220-year history.

She is President Barack Obama's first appointment to the influential court, which has shaped many of the country's laws on polarizing issues like abortion and the death penalty. As a successor to liberal Justice David Souter, who retired, she is not expected to alter the nine-member court's ideological balance.

Sotomayor took the second of two oaths of office Saturday from Chief Justice John Roberts in an ornate conference room, beneath a portrait of the legendary Chief Justice John Marshall. Her left hand resting on a Bible that was held by her mother, Celina, Sotomayor pledged to "do equal right to the poor and to the rich."

Minutes earlier, she swore a first oath in a private ceremony in the room where the justices hold their private conferences.

Sotomayor wore a cream-colored suit and her right ankle, fractured in a fall a couple of weeks after her nomination to the court, was unbandaged. Her 60 or so guests included Justice Anthony Kennedy, White House counsel Greg Craig and other members of the Obama administration team that helped prepare her for her Senate confirmation hearings, family and friends.

Roberts, wearing his black judicial robe, said that once the oaths were done, Sotomayor could "begin work as associate justice without delay."

Obama scheduled a White House reception for Sotomayor on Wednesday.

Joins Ginsburg
The 55-year-old Sotomayor has been a federal judge for 17 years. Obama nominated her for the lifetime appointment in May, and the Senate confirmed her on Thursday.

She will join Justice Ruth Bader Ginsburg as the only other woman currently serving o the court.

Sotomayor is the daughter of Puerto Rican parents who was raised in a housing project in New York City's gritty South Bronx neighborhood and educated at the elite universities Princeton and Yale before going on to success in the legal profession and then the federal bench.

Replacing Souter
The new justice can now get to work, although the Supreme Court won't hear arguments until Sept. 9, in a key campaign finance case. The entire court will convene a day earlier, however, for a formal ceremony to welcome Sotomayor.

Video   Latinos hail Sotomayor’s rise Aug. 8: From the streets of Manhattan to college campuses in California, Latinos are proudly celebrating the historic swearing in of Supreme Court Justice Sonia Sotomayor. NBC’s George Lewis reports. Nightly News

Sotomayor also will be learning the quirky customs of the highest court in the land. As the newcomer she will take notes and answer the door when the justices have private meetings, including one in late September at which they dispose of a couple thousand appeals.

A former clerk to Sotomayor's predecessor, Souter, says that first case in September could get her thinking about the biggest change anyone faces in becoming a justice, the far-reaching impact of some Supreme Court decisions.

There are few easy questions that come the court's way," said Meir Feder, the former Souter clerk who is now a partner at the Jones Day firm in New York "You're not applying settled law," Feder said, "because if it's settled, it shouldn't get there in the first place."

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