At first blush, this has been a relatively harmonious year on the Supreme Court. The Court closed the term on Monday with its greatest share of unanimous decisions in decades.
So it is not surprising that USA Today recently headlined an article “At the Supreme Court, an uptick in unanimity.” Or that last week, former acting solicitor general, Neal K. Katyal, wrote in The New York Times of the “remarkable achievement” that about two-thirds of the Court’s rulings this term have been unanimous. “Even in this hyperpartisan age,” he concluded, “there is a difference between law and politics.”
Yet the Supreme Court has proven susceptible to the same polarization that afflicts all of Washington, and this year’s unanimous rulings mask enduring divisions. The Roberts Court remains the most polarized in American history, continuing a rise in Court division that has been developing for more than a half century. Some, like Katyal, are celebrating this year as a sign that this trend has turned. Only 15 percent of the Court’s rulings this term were 5-to-4 decisions—half the share of one-vote majorities from last year.
We’ve seen this fluctuation before. In 2005, John Roberts’ first year as chief justice, 14 percent of the Court’s rulings broke along a 5-to-4 split. The next year registered the highest share of one-vote majority decisions in Court history, 34 percent. The year after, one-vote majorities receded to 16 percent, and veteran Court reporter Linda Greenhouse asked, “Where have all the 5-to-4 decisions gone?” Yet the following year, the share of one-vote majorities nearly doubled. In fact, since 1801, Roberts has presided over three of the four Court terms where 5-to-4 majorities decided at least 30 percent of the rulings.
Generally, unanimous decisions are a less reliable metric of Court consensus than 5-to-4 decisions, which tend to capture the most significant cases, if not also the most partisan.
“Decisions are unanimous when the ideological stakes are not large enough to lead a Justice who disagrees with the majority to dissent,” according to a 2012 study by Lee Epstein, William Landes, and Richard Posner.
“The unanimity this term, in my view, really reflects case selection,” says Epstein, who studies Court behavior as a professor at Washington University in St. Louis. She compared this term’s case selection to the previous three terms. “The fraction of civil liberties cases this term is significantly lower,” she added. “And the more civil liberties cases, the less likely decisions are to be unanimous.”
The Court’s final two decisions this term captured how, even in a year of high unanimity, many of America’s most important legal disputes are still settled by one vote. On Monday, a 5-to-4 majority ruled that some public sector employees could not be required to pay fees to unions representing them, a blow to organized labor. The Court also ruled, again by a 5-to-4 divide along ideological lines, that President Obama's signature health care law cannot mandate that closely held private companies provide health insurance coverage for contraceptives if the owners have religious objections—strengthening earlier decisions that have vested corporations with the constitutional rights of citizens.
Under Roberts, some of these decisions have defied conventional ideological alignments. Yet in total, about two-thirds of the Roberts Court’s 5-to-4 rulings have sorted along predictable ideological camps, according to data collected by SCOTUSblog. Under Roberts, one-vote conservative majorities have struck down the core of the 1965 Voting Rights Act, upheld an individual’s right to gun ownership, limited an employee’s ability to file a pay discrimination case, allowed unlimited corporate and union campaign spending, and limited class-action suits.
Even at 15 percent, this year’s lower share of 5-to-4 rulings is three percentage points more than the average under Earl Warren. Since then, 5-to-4 splits have risen from Warren Burger’s Court (17 percent) to William Rehnquist’s Court (20.5 percent) to the Roberts’ Court (22 percent). By comparison, from 1801 to the outset of the Second World War, one-vote majorities resolved less than 2 percent of the Court’s total decisions.
To be sure, the nine justices have reached a consensus on some significant cases this term. But even this unanimity can cloak fierce discord. Sometimes consensus means consensus, as with the Court decisions requiring police to obtain a warrant before searching a suspect's cellphone. Yet other unanimous decisions, such as the case striking down buffer zones around abortion clinics, demonstrate that on this Court, consensus can also amount to opposition by any other name. “I prefer not to take part in the assembling of an apparent but specious unanimity,” Justice Antonin Scalia wrote in his concurring opinion on that case, which was joined by Justices Clarence Thomas and Anthony Kennedy. Scalia’s “concurrence” disagreed with Roberts’ opinion that the abortion law was “content neutral” and wrote that Roberts’ opinion preserved “the ability of jurisdictions across the country to restrict antiabortion speech without fear of rigorous constitutional review.”
The unanimous ruling that limited the president's power to make recess appointments betrayed the same division. The Court agreed that the president acted unconstitutionally when he circumvented Republican opposition by appointing members to the National Labor Relations Board during a three-day Senate recess. But the justices differed on their reasoning, and reasoning can shape law. Justice Antonin Scalia, writing on behalf of four conservative members of the Court, wrote that the decision was a “real tragedy” because “the majority replaces the Constitution’s text with a new set of judge-made rules,” among other protestations.
This polarization has not escaped the public eye. In 1946, as polarization on the Court began to increase, about four in 10 Americans told Gallup that they believe “the Supreme Court decides many questions largely on the basis of politics.” Last week, Rasmussen Reports found that about six in 10 Americans now believe “most Supreme Court justices have their own political agenda.” Gallup reported Monday that like all three branches of government, views of the Supreme Court have reached new lows. Only 30 percent of the public remains confident in the Court, the lowest rating since the question was first asked in 1973.
Scholars have found that ideology “matters more in the Supreme Court than in the court of appeals,” according to a 2009 study by Posner and Landes. And as the Court has become more polarized, it has become more reliant on “minimum-winning coalitions.” These 5-to-4 splits tend to effectively vest one judge—most often Anthony Kennedy on this Court—with the power to decide headline decisions, undermining the Court’s authority as an apolitical body of “supreme” justice.
Research indicates that 5-to-4 decisions are also the most likely to be overturned by later courts. One-vote majorities are the “flashier opinions” and “tend to create more extreme law because it’s a more homogeneous group of justices,” Epstein says. “The Court can do more when you only have to get five votes.”