Jeffrey Rosen interviewed Supreme Court Chief Justice John Roberts at the end of his first term way back in 2006. Recalling that interview in a New Republic article, Rosen offers this analysis of why a conservative like Roberts would vote in favor of Obamacare:
Roberts returned repeatedly to one theme: his desire to restore the bipartisan legitimacy of the Supreme Court. In Roberts’ view, the Court was losing respect with the public because it issued too many rulings along partisan lines. “I do think the rule of law is threatened by a steady term-after-term focus on five–four decisions,” he said. “I think the Court is also ripe for a similar refocus on functioning as an institution,” he told me, “because if it doesn’t, it’s going to lose its credibility.”
Roberts said he had been inspired by the example of his greatest predecessor, John Marshall. “He could easily have got on the Court and said, ‘I’m the last hope of the Federalists: We’re out of Congress, we’re out of the White House, and I’m going to pursue that agenda here,’” he said. “But instead he said, ‘No, this is my home now, this is the Court, and we’re going to operate as a Court, and that’s important to me.’”
As we talked, it became clear that Roberts saw the promotion of consensus in service of the Court’s long-term interests as the greatest test of a successful chief justice. “I think judicial temperament is a willingness to step back from your own committed views of the correct jurisprudential approach and evaluate those views in terms of your role as a judge,” Roberts explained. “A justice is not like a law professor, who might say ‘This is my theory of this, and this is what I’m going to be faithful to and consistent with, and in twenty years we’ll look back and say, I had a consistent theory of the First Amendment as applied to a particular area,’” he said. “Coherence in the Court’s jurisprudence is more important than coherence in each individual justice’s jurisprudence.” He added, in a remark that now seems prescient, “I would like to think, looking back, that my opinions show a concern about the legitimacy of what we’re doing is an important part of the inquiry in each case.” The fact that Roberts was willing to defend the Court’s institutional legitimacy in the health care case confirms that he meant what he said."