Many people on both the left and right expect Roberts to return to the fold and side with the conservative justices in the new term's big cases. If they're right, the spotlight will be back on Justice Anthony Kennedy, whose vote typically is decisive in cases that otherwise split the court's liberals and conservatives.
But Roberts will be watched closely, following his health care vote, for fresh signs that he's becoming less ideologically predictable.
It may be that the dramatic health care decision presages "some shift in his tenure as chief justice," said Steve Shapiro, the American Civil Liberties Union's national legal director. "Or does it give him cover to continue to pursue a conservative agenda?"
The first piece of evidence could be in the court's consideration of the University of Texas' already limited use of race to help fill its incoming freshman classes, which comes before the court Oct. 10. The outcome could further limit or even end the use of racial preferences in college admissions.
Roberts has expressed contempt for the use of race in drawing legislative districts, calling it "a sordid business, this divvying us up by race," and in assigning students to public schools, saying that "the way to stop discrimination on the basis of race is to stop discriminating on the basis of race."
The written arguments submitted by both sides in the Texas case leave little doubt that Kennedy, not Roberts, holds the prized vote. The challengers of the Texas program and the university itself cite Kennedy's prior writings on affirmative action a combined 50 times.
The court also is expected to confront gay marriage in some form. Several cases seek to guarantee federal benefits for legally married same-sex couples. A provision of the 1996 Defense of Marriage Act deprives same-sex couples of a range of federal benefits available to heterosexual couples.
Several federal courts have agreed that the provision of the law is unconstitutional, a situation that practically ensures that the high court will step in.
A separate appeal asks the justices to sustain California's Proposition 8, the amendment to the state constitution that outlawed gay marriage in the nation's largest state. Federal courts in California have struck down the amendment.
Once again, many legal analysts expect Roberts essentially to be against gay marriage. "The outcome clearly turns on how Anthony Kennedy votes," said Georgetown University law professor Michael Seidman.
The justices may not even consider whether to hear the gay marriage issue until November.
Another hot topic with appeals pending before the high court, and more soon to follow, is the future of a cornerstone law of the civil rights movement.
In 2006, Congress overwhelmingly approved, and President George W. Bush signed, legislation extending for 25 more years a critical piece of the Voting Rights Act. It requires states and local governments with a history of racial and ethnic discrimination, mainly in the South, to get advance approval either from the Justice Department or the federal court in Washington before making any changes that affect elections.
The requirement currently applies to the states of Alabama, Alaska, Arizona, Georgia, Louisiana, Mississippi, South Carolina, Texas and Virginia. It also covers certain counties in California, Florida, New York, North Carolina and South Dakota, and some local jurisdictions in Michigan and New Hampshire. Coverage has been triggered by past discrimination not only against blacks, but also against American Indians, Asian-Americans, Alaskan Natives and Hispanics.
The court spoke skeptically about the provision in a 2009 decision, but left it mostly unchanged. Now, however, cases from Alabama, North Carolina, South Carolina and Texas could prompt the court to deal head on with the issue of advance approval. The South Carolina and Texas cases involve voter identification laws; a similar Indiana law was previously upheld by the court.
It is unclear when the justices will decide whether to hear arguments in those cases. Arguments themselves would not take place until next year.
Yet there still is a chance that the court could become enmeshed in election disputes, even before the ballots are counted. Suits in Ohio over early voting and provisional ballots appear the most likely to find their way to the justices before the Nov. 6 election, said Richard Hasen, an election law expert at the University of California at Irvine law school.
Among other important cases already on the court's docket:
• A high-stakes dispute, to be argued first thing Monday, between the business community and human rights advocates over the reach of a 1789 law. The issue is whether businesses can be sued in U.S. courts for human rights violations that take place on foreign soil and have foreign victims.
• A challenge to the use of drug-sniffing dogs in two situations. Florida police used a marijuana-sniffing dog's alert at the door of a private home to obtain a search warrant to look inside the house. The question is whether the dog's sniff itself was a search. A separate case looks at the reliability of animals trained to pick up the scent of illegal drugs.
• A challenge to the detention of a man who police picked up a mile away from an apartment they had a warrant to search. Occupants of a home may be detained during the search for the safety of officers, but this case tests how far that authority extends away from the place to be searched.
• Environmental disputes involving runoff from logging roads in Oregon and water pollution in Los Angeles.
Paul Clement, the Republican lawyer who lost the health care case and could again be before the justices on gay marriage and voting rights, said last term punctured the notion that in close cases, the court goes where Kennedy wants.
"We've all been reminded that's not always the case," he said.
The idea that could be tested this term is whether Roberts' concern for the court as an institution that is apart from politics will influence his votes, or at least his reasoning, in the year's biggest cases.
The justices of the Supreme Court
The justices of the Supreme Court, in order of seniority, with their age, the presidents who appointed them, and when they took their seats on the high court. The chief justice is considered the most senior, regardless of the length of tenure:
Chief Justice John Roberts, 57 • Appointed by President George W. Bush, September 2005
Justice Antonin Scalia, 76 • President Ronald Reagan, September 1986
Justice Anthony Kennedy, 76 • Reagan, February 1988
Justice Clarence Thomas, 64 • President George H.W. Bush, October 1991
Justice Ruth Bader Ginsburg, 79 • President Bill Clinton, August 1993
Justice Stephen Breyer, 74 • Clinton, August 1994
Justice Samuel Alito, 62 • George W. Bush, January 2006
Justice Sonia Sotomayor, 58 • President Barack Obama, August 2009
Justice Elena Kagan, 52 • Obama, August 2010.
Big cases for new Supreme Court term
A look at cases the Supreme Court already has agreed to hear and other top cases in the pipeline
Racial preferences • In Fisher v. University of Texas, to be argued Oct. 10, the court will weigh Texas' limited use of race to help fill out its incoming classes. The outcome could result in a major cutback in the use of racial preferences at the nation's colleges.
Accountability for human right abuses • The justices will consider whether American courts may be used by foreign victims to sue over human rights violations abroad. The case of Kiobel v. Royal Dutch Petroleum, to be argued on Monday, concerns claims that the oil giant Shell was complicit in atrocities committed by the Nigerian government against its citizens in the oil-rich Niger delta.
Drug-sniffing dogs • Two disputes involving drug-sniffing dogs will be heard by the court on Halloween. In one, the question is whether a dog brought to the front door of a home to sniff for marijuana amounts to a search. In the other, the court will consider a dog's reliability and qualifications as a drug-sniffing animal in a case involving a traffic stop and a warrantless search that found the ingredients for making methamphetamines in a pickup truck.
Fighting terrorism • The government is trying to shut down a constitutional challenge to a law that lets the United States eavesdrop on overseas communications. Lawyers, journalists and human rights advocates filed a lawsuit that objected to the latest version of the Foreign Intelligence Surveillance Act. The issue at the high court, to be argued Oct. 29, is whether the law's challengers are entitled to make their case in federal court.
The following issues probably will be heard this term:
Gay marriage • The justices are expected to take up gay marriage in at least one of the many appeals pending at the high court. Several lower federal courts have struck down as unconstitutional a provision of the 1996 Defense of Marriage Act that denies federal benefits, including favorable tax treatment and health benefits, among many others, to legally married same-sex couples. The court almost always has the last word when federal laws are struck down. A separate appeal involves California's ban on gay marriage, ruled unconstitutional by federal courts.
Voting right act • Several appeals ask the court to invalidate a cornerstone of civil rights era legislation, a provision of the Voting Rights Act that requires all or parts of 16 states, most in the South and all with a history of past discrimination, to get approval from the Justice Department or the federal court in Washington before instituting any changes affecting elections and voting. Some justices expressed skepticism about the need for this measure in a 2009 decision that sidestepped a definitive ruling.
The Associated Press