On one level, Justice Souter's retirement, expected in late June, will not significantly alter the balance of power between liberal and conservative wings on the high court. Though nominated to the court by a Republican president, the first President Bush, Souter turned out to be a reliable liberal vote.
But that does not mean Souter's replacement won't be significant. All eyes will be on Mr. Obama, as factors such as gender, age, ethnicity, and intellectual heft are considered. That Souter's replacement will fit into the liberal wing of the court goes without saying. But just how left-of-center Obama wants to go in his selection is an open question. Obama has disappointed his liberal political base before – most recently, in boosting his commitment to the war in Afghanistan – and the heat is already on to select a left-wing analog to Justice Antonin Scalia.
"He faces a lot of pressures, because the left will want him to anoint one of its own to solidify a new direction in the court," says Darrell West, director of Governance Studies at the Brookings Institution. "Others will worry that that ignites a culture war that engulfs his presidency."
Chances are Obama selects someone like himself – calm, smart, and thoughtful, Mr. West adds. Note that "fire-breathing liberal" does not appear in that list. As president of the Harvard Law Review in the early '90s, Obama was known for being fair to all sides, to the point where people of disparate views sometimes thought he agreed with them.
In a surprise appearance during the White House’s press briefing Friday, Obama made the first formal announcement of Souter’s decision to retire. “I just got off the telephone with Justice Souter, and so I would like to say a few words about his decision to retire from the Supreme Court,” Obama said.
After praising the justice’s work ethic and integrity, Obama outlined how he intends to select Souter’s replacement. “I will seek someone who understands that justice isn’t about some abstract legal theory or footnote in a casebook. It is also about how our laws affect the daily realities of people's lives – whether they can make a living and care for their families, whether they feel safe in their homes and welcome in their own nation,” he said. “I view that quality of empathy, of understanding and identifying with people's hopes and struggles, as an essential ingredient for arriving at just decisions and outcomes.”
He added, “As I make this decision, I intend to consult with members of both parties, across the political spectrum.”
The president said he hoped a new Supreme Court justice could be sworn in by the beginning of the new term in October.
The name long floated as front-runner for Obama's first pick is Elena Kagan, 49, former dean of Harvard Law School, who was confirmed as the nation's first female solicitor general on March 19. The Senate vote was 61 to 31.
Given that the current court contains only one woman, Justice Ruth Bader Ginsburg, it is widely assumed that Obama will address that imbalance by selecting a woman. Two other frequently mentioned names are Diane Wood, 58, and Sonia Sotomayor, 54, both federal appeals court judges.
But it's Ms. Kagan's lack of strong ideological profile that could weigh in favor of waiting for a subsequent high court nomination, which Obama is almost certain to have. Kagan has never served as a judge and has barely gotten her feet wet as solicitor general. If the assumption is that she would be an easy confirmation, Obama may hold onto to her for later, when chances are he will not be as popular as he is now (polling consistently in the 60s on job approval).
Given that the Senate Democratic caucus has just gained a new member – the party-switching Arlen Specter of Pennsylvania – and is likely to gain its 60th vote this summer, when Al Franken is expected to win the contested Minnesota Senate race, Obama has a strong hand to play when his nominee reaches the Senate for confirmation. Sixty votes are required to halt debate in the Senate, allowing a nomination to proceed to final passage.
Two high-profile liberal female legal scholars being mentioned are Pamela Karlan, born in 1959, and Kathleen Sullivan, born in 1955. Both teach law at Stanford University in Palo Alto, Calif. Given all the other pressing issues currently before the president, however, he may decide that now is not the time to try to push through a nomination that would be especially contentious.
Obama will also face pressure to nominate the court's first Hispanic – a constituency that voted heavily for him last November. That points to Judge Sotomayor. But she may be vulnerable to prolonged and vigorous conservative attacks, because of her role last year on a three-judge appeals court panel that upheld the invalidation of a civil-service test because no black candidates scored high enough for a promotion.
The case was argued last week at the US Supreme Court, and a decision is expected by late June. Some analysts predict that Sotomayor and her colleagues will be overruled.
As for the prospect of a liberal Justice Scalia, time will tell.
"It's going to be hard to find people who are ideologically liberal versions of Scalia, because what that would mean, I suppose, is a Thurgood Marshall or a Bill Brennan, and American law has moved since the 1970s on a lot of issues," says Michael Dorf, a constitutional law professor at Cornell Law School in Ithaca, N.Y.
"I think it will be very hard to find someone on the liberal side who is an ideological liberal in the way that Scalia is an ideological conservative," Professor Dorf says. "Part of what people want is someone who is temperamentally a fighter in the way that Scalia is. Karlan is someone who fits that bill."
"It is hard to find people who are simultaneously ideological, witty, and charming. Scalia is all those things, but Karlan is also."
Already, the battle has been joined over Souter's replacement.
"Based on the appointments at the Department of Justice, it's clear that President Obama will name a Supreme Court nominee who will embrace an extremely liberal judicial philosophy," says Jay Sekulow, chief counsel for the American Center for Law and Justice. "There's no illusion here – President Obama is poised to reshape the nation's highest court."
"President Obama now has the opportunity to nominate someone worthy of his own historic legacy," she said in a statement. "The president can look to a broad array of legal talent to select a nominee who not only has an excellent record in the law, but also a respect for core constitutional values and a commitment to equal justice for all, not just a few."