By MARK SHERMAN
WASHINGTON (AP) - Chief Justice John Roberts could have taken down the entire, massive health care law that his fellow Republicans deride as "Obamacare." He could have prevented the Supreme Court decision that largely disabled the most disputed aspects of Arizona's crackdown on illegal immigrants.
He didn't do either, and in the process surprised (or dismayed) longtime court observers of every political stripe.
Those two outcomes in the finals days of his seventh year on the court offer some clues for reassessing what kind of chief justice Roberts is and intends to be. Is he no longer the rock-ribbed conservative loved by supporters and jeered by opponents? Has he become a pragmatic leader mindful of the court's place in history? Is he more canny, but still solidly conservative?
The measure of a justice is best taken after decades of service, rather than a few years. At age 57, Roberts could lead the court for another quarter-century.
But at the very least, the end of the Roberts Court's most consequential term already is leading to revised, and in some cases more nuanced, appraisals of his leadership.
Erwin Chemerinsky, a liberal scholar who is dean of the law school at the University of California at Irvine, announced that the era of the Roberts Court had begun. "He authored the opinion in the most important case in his seven years on the court, and did so against what was expected," Chemerinsky said.
In truth, Roberts' vote to uphold President Barack Obama's health care law was not so much a surprise.
He long had been counted among the possible votes to uphold the law. But it was widely assumed that if Roberts ultimately voted for it, so too would Anthony Kennedy, most often the decisive vote in closely fought cases. It was only the second time in his tenure that Roberts provided the deciding vote for the side favored by the court's liberals.
Up until now, it had been the Kennedy Court, Chemerinsky said, "This year, it was the Roberts Court."
Had Roberts gone the other way, the court would have wiped away the entire health care overhaul, which is the outcome embraced by dissenting Justices Samuel Alito, Antonin Scalia, Clarence Thomas and Kennedy.
Instead, he said the individual insurance requirement at the heart of the law could be upheld as a tax. At the same time, he rejected administration arguments that the mandate was justified by the Constitution's clause giving Congress power over interstate commerce, which has been the authority for most federal programs since the New Deal.
Some legal scholars suggest Roberts produced an essentially conservative opinion with a liberal outcome.
Neal Katyal, the former acting solicitor general who argued the Obama administration's side in the health care cases in several appeals courts, said that Roberts' majority opinion opened the door to potentially important changes in the law that could restrict federal power as it has been understood since the New Deal.
Ilya Somin, a George Mason University law professor, said on the Volokh Conspiracy legal blog that the health care case "gives supporters of limits on federal power some useful ammunition, despite also dealing us a painful defeat."
In addition, Roberts' ruling has helped refocus the public debate over the law and gave Republican opponents ammunition for calling it a big tax increase they would try to repeal.
Just three days earlier, Roberts, joined by Kennedy this time, sided with three liberal justices in the Arizona immigration case. Justice Elena Kagan, one of the court's liberals, did not take part because of her previous involvement as solicitor general, when she was the Obama administration's top Supreme Court lawyer.
Roberts joined in every word of Kennedy's majority opinion that struck down three contentious provisions of the law, but allowed one to go forward _ the requirement that police check the immigration status of people they stop for other reasons.
Roberts could have sided with the conservatives who favored allowing other provisions to take effect, but that would have left the court divided 4-4, a distasteful outcome because it amounts to a waste of the justices' time.
What's more, Roberts might have reasoned that Kagan probably would side with the other liberal justices and Kennedy in some future immigration case over similar state laws that she could take part in. Such a case down the road probably would produce an outcome similar to what the court achieved last week in the Arizona case. But if Roberts stuck with the conservative justices, that scenario would have deprived him of a chance to try to influence the majority opinion.