By Robert Barnes Washington Post

The Supreme Court begins its new term Monday with unprecedented diversity among its members but also the potential for a split that would for the first time in decades reflect the partisan ideologies of the presidents who appointed them.
The defining story of the new term may be twofold: the rapid evolution of the court headed by Chief Justice John G. Roberts Jr. - the first of four new justices in the past five years - and what the change in justices means for the courts image and actions.
The most obvious will be the presence of three women. Justice Ruth Bader Ginsburg who had hoped for such a day when she was confirmed 17 years ago said it will send a powerful signal about the nations governance when she and Justices Sonia Sotomayor and Elena Kagan take their places.
The major difference is going to be the public perception of where women are in the justice system the 77-year-old Ginsburg said in a recent interview in her chambers. The three of us we are here to stay.
When the schoolchildren file in and out of the court and they look up and they see three women then that will seem natural and proper - just how it is.
But another change could be problematic for a court that goes to great lengths to distinguish itself from the political branches of government.
Two solid members of the courts left David H. Souter and John Paul Stevens have departed in the past 16 months. But because they were appointed by Republican presidents the courts conservative and liberal factions were never described as a partisan divide. That could change with their replacements being named by President Obama.
I think rarely in the 20th century was there so obviously a partisan and ideological split on the court said Barbara Perry senior fellow at the University of Virginias Miller Center of Public Affairs and a scholar who has studied the court. There will be five appointees by Republicans who are very conservative or at least moderately conservative and four Democratic appointees who are liberal or moderate liberals.
At risk said Columbia University law professor Nathaniel Persily is the distinction the justices make about the courts status as something apart from the nations increasingly fractious and partisan politics.
A large segment of the population already looks at the court as being made up of political actors said Persily who noted that the change comes on the 10th anniversary of one of the courts most polarizing decisions Bush v. Gore.
Additional damage could come if what he called elite commentators analyzing future decisions emphasize the courts partisan divide rather than its ideological differences.
If for instance liberals start trashing the Supreme Court as just another Republican institution Persily said.
Those differences may not be as stark in the coming term which at this point doesnt feature any of the hot-button social issues that most often divide the court. Missing from the courts docket are abortion race- or sex-based discrimination policies and frontal challenges to the death penalty or gun rights.
But divisive issues are on the horizon. The battle over same-sex marriage is working its way through the legal system. Partisan legal fights will spring from states redrawn political districts. And direct confrontations with the Obama administration and Congress will come if the health-care overhaul and challenges to the regulation of the nations financial institutions make their way to the court.
Obama has seemed eager to categorize the court as a foe. He criticized the court before the nation during the State of the Union address this year for its 5 to 4 decision in Citizens United v. Federal Election Commission which allowed unlimited political spending by corporations and unions.
Justice Samuel A. Alito Jr. was seen on camera objecting to the presidents characterization of the courts decision and Roberts later called Obamas decision to criticize the court while it sat silently in the House chambers very troubling.
But Obama has continued to personalize his disagreements with the court saying for instance that his appointments will look out for the average American rather than corporate interests.
In a recent Rolling Stone interview he blamed the court for Democratic troubles in the upcoming elections. The partys candidates are under attack from groups the Roberts Court says can spend with impunity without disclosing where their moneys coming from Obama said.
U-Va.s Perry said the back-and-forth is bad for both branches but probably worse for the court.
People expect the president and Congress to be political she said. They expect better of the court and the court usually lives up to that image.
Lee Epstein a political scientist at the Northwestern University Law School said that for decades the court has had at least one or two justices whose jurisprudence seems at odds with the party of the president who appointed them with Souter and Stevens only the most recent.
Justice Anthony M. Kennedy appointed by President Ronald Reagan at times sides with the courts liberals most notably on issues such as punishing juveniles and gay rights.
But more often in close cases he sides with the courts conservatives. And if Kagan becomes a reliable vote for the liberal side as Sotomayor did her first year those 5 to 4 decisions will now be Republicans against Democrats Epstein said.
Thats a very different story about the court she said. The partisan story resonates with people more than the ideological.
The justices agree it can be a problem. Justice Stephen G. Breyer promoting his new book about the courts workings said he worried that the biggest threat to the courts credibility is that the nine justices are seen as junior-varsity politicians.
But Breyer and other justices often point out that a majority of the courts decisions each year are unanimous or lopsided. And they say that justices explain in every case why their view of the law commands the outcome theyve reached.
Members of Congress can vote yes or no Ginsburg said. Justices have to say why.
She also said the public misunderstands the courts role.
People sometimes ask me When is the court going to take up such and such issue? Ginsburg said. Thinking that we have an agenda just as the administration does . . . not appreciating that we are a wholly reactive institution.
Ginsburg is also often asked what difference it will make in the courts deliberations that women will account for a third of the justices. She thinks it will matter only in rare cases.
In the typical case - that Im a woman that I was raised a Jew - that doesnt play into the decision she said.
She points out that in her tenure on the court the justice she most often agreed with was Souter not Sandra Day OConnor.
Studies have shown the same. In a study of appellate court judges Epstein and others found no real difference in how men and women decided cases in 12 of 13 areas of law. The exception Epstein said was in cases charging sex-based employment discrimination.
Ginsburg offered such a case as an example of an insight she had that her male colleagues lacked.
The case involved Lilly Ledbetter the Alabama tire plant manager who the court said in a 5 to 4 decision had filed her challenge of unequal pay too late. The majority said the law required Ledbetter to file a complaint as soon as she suspected she was being paid less than men.
Ginsburg read her dissent from the bench and called on Congress to change the law. The resulting legislation became the first bill Obama signed.
Every woman of my age had a Lilly Ledbetter story Ginsburg said. And so we knew that the notion that a woman who is in a nontraditional job is going to complain the first time she thinks she is being discriminated against - the one thing she doesnt want to do is rock the boat to become known as a complainer.
Her female colleagues - Sotomayor 56 and Kagan 50 - are of a different generation. Ginsburg now predicts a day when a majority of the justices are women.
It wasnt possible earlier. . . . In my generation women were about 3 percent of the lawyers Ginsburg said. But now women are doing everything.