As I approached the U.S. Supreme Court on my way to this term’s last Decision Day, I suddenly found myself literally caught between two extreme factions in the health-care debate.  One group, led by two belly dancers and a compatriot carrying a bed-sheet labeled “Single Payer,” shimmied toward two bearded anti-Obamacare protestors who shouted at the gyrating dancers, “Communists!” and “Single payer is socialism!”  Momentarily stuck between the zealots, I felt like Chief Justice Roberts, trying to find an exit strategy.

An hour later I sat in my prized seat inside the churchlike courtroom and marveled at the chief’s painstakingly crafted opinion, upholding the Affordable Care Act (ACA), while attempting to extricate the high tribunal from a political quagmire.  Much has been made of this patently conservative jurist’s reaching a liberal outcome.  Is John Roberts the next David Souter, Harry Blackmun, William Brennan, or Earl Warren—his Supreme Court predecessors who disappointed their appointing presidents by swinging to the other side of the ideological spectrum?  Probably not.  One liberal decision—albeit in a landmark case—does not a judicial career make.  In fact, on the larger issues at stake in the ACA litigation (Congress’ commerce, “necessary and proper,” and spending powers), the chief reached conservative conclusions.  It remains to be seen whether his limits on legislative prerogatives are mere “blips,” as Justice Ruth Bader Ginsburg in her stinging dissent predicted, or lasting obstacles to future liberal policy initiatives.

More important, Roberts’ opinion, partially joined by the Court’s liberal quartet (Ginsburg, Breyer, Sotomayor, and Kagan), reflects his historic view of the chief justice’s role.  One of his first acts after confirmation was to send staff members to Chief Justice John Marshall’s Richmond, Virginia home to retrieve the fourth chief justice’s judicial robe on display there.  Roberts wanted to model his robe after the “great chief justice,” as Marshall is called.  The act speaks volumes.  Roberts’ mentor, William Rehnquist, who as an associate justice was dubbed the “Lone Ranger” for his many solo dissents, modeled his chief justice robe after a Gilbert and Sullivan operetta character (complete with four gold metallic stripes on the sleeves!).  Assuming the Court’s center chair in the wake of the polarizing Bush v. Gore decision, Roberts explained to George Washington University law professor Jeffrey Rosen that he hoped to increase collegiality and unanimity among the nine justices.  Unanimity produces stability in the law, he reasoned, which, in turn, leads to more public respect for the tribunal. 

With the Court’s most recent approval ratings dropping to 44%, and three-quarters of Americans surveyed believing that the justices would follow their partisan inclinations in deciding the health-care case, Chief Justice Roberts faced a dilemma.  Siding with his conservative soul mates (Scalia, Kennedy, Thomas, and Alito) would confirm the view that the Court is just another political institution.  Instead, he assumed the uncharacteristic position of swing voter, casting the deciding vote between four liberals and four conservatives.

When the chief is in the majority, by tradition he assigns the author of the Court’s opinion.  Roberts chose to self-assign, putting the chief’s imprimatur on the controversial ruling.  In addition, to avoid a completely partisan result, he cast his deciding vote with the liberals to uphold the ACA, while incorporating elements from the conservative bloc’s dissent.

From my vantage point in the second row, I could see that the chief’s Solomonic decision had taken its toll on his normally imperturbable and confident visage, especially when Justice Kennedy attacked him from the right and Justice Ginsburg fired salvos from the left.  Neither the chief’s heart nor head seemed at ease.  Putting duty, leadership, and history ahead of ideology exacts a cost.  In his Senate confirmation hearings, John Roberts famously described a jurist’s job as that of the umpire, neutrally calling balls and strikes.  But if both teams are unhappy with the calls, everyone boos.

Beyond the Court’s arena, however, President Obama has emerged from this high-stakes game a winner, at least in the short run.  He centered his victorious 2008 campaign on creating a national health-care policy, was elected on this platform by a clear majority, saw it pass both houses of Congress (even if along partisan lines), urged the U.S. Supreme Court to rule on the law, and now celebrates its declaration of constitutionality by a conservative chief justice.

But the partisan fault lines in Congress and across the street at the Court reflect those in the electorate, and Obama will have to face the consequences of his judicial victory—a reinvigorated GOP base, Tea Party, and Romney candidacy.  Chief Justice Roberts and his narrow majority affirmed the ACA’s euphemistically labeled “shared responsibility payment” as a tax.  Now there’s a winning campaign slogan for the president: “The Supremes Upheld My Tax!”

Not since the New Deal era has the U.S. Supreme Court’s rulings on an incumbent president’s policies had such an impact on his reelection.  FDR won a landslide victory in 1936, in part, because the Supremes ruled against him.  President Obama faces the ironic prospect that he could lose the race because the Court ruled for him.

Barbara A. Perry is a Senior Fellow in the Miller Center’s Presidential Oral History Program.  You can follow her on Twitter @tweetbriar.