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.