The Washington PostDemocracy Dies in Darkness

Opinion Does campus diversity justify affirmative action? Our study says yes.

Students protest in support of affirmative action outside the Supreme Court in 2013 during the hearing of Schuette v. Coalition to Defend Affirmative Action. (Andrew Burton/Getty Images)
5 min

Adam Chilton and Jonathan Masur are law professors at the University of Chicago. Justin Driver is a law professor at Yale University. Kyle Rozema is a law professor at Washington University.

This month, the Supreme Court will hear oral arguments in two cases that pose the starkest threats ever to affirmative action in higher education. Central to those cases, involving admissions programs at Harvard College and the University of North Carolina, will be the value of campus diversity, which is the sole justification for affirmative action that the court has endorsed.

The notion that racially diverse student bodies improve campus intellectual life has been roundly attacked by both liberals and conservatives. But the Roberts court should not be quick to dismiss diversity’s value and dismantle affirmative action. Because we have evidence that diversity works.

Justice Lewis F. Powell Jr. placed diversity at the center of affirmative action debates in 1978, when he provided the critical fifth vote upholding the constitutionality of some race-conscious admissions policies. Unlike the other four justices who supported race-conscious policies as a way of redressing racial injustice, Powell alone favored permitting admissions officers to consider applicants’ race for the purpose of attaining a diverse student body. Diversity, Powell wrote, improved “the atmosphere of speculation, experiment and creation” that is “so essential to the quality of higher education,” and he contended: “The nation’s future depends upon leaders trained through wide exposure to the ideas and mores of students as diverse as this Nation of many peoples.”

Powell’s views eventually became the law of the land, as the court has repeatedly upheld challenges to affirmative action by citing his diversity rationale. Equally important, efforts to promote diversity have spread to workplaces, organizations and many other settings — and have become woven into the American social fabric.

Nevertheless, opponents of affirmative action have often cast doubt on the existence of verifiable evidence to support the diversity rationale. Professor Peter Schuck of Yale University has called it “empirically tenuous and theoretically implausible.” Noted economist and commentator Thomas Sowell has gone further: “Nothing so epitomizes the politically correct gullibility of our times as the magic word ‘diversity.’ The wonders of diversity are … confirmed in the august chambers of the Supreme Court. … Have you ever seen one speck of hard evidence to support the lofty claims?” Even some supporters of affirmative action have questioned the empirical foundation of diversity. Harvard professor Randall Kennedy has confessed: “I remain doubtful about social scientific ‘proof’ of diversity’s values.”

Paul Butler: I once told a Supreme Court justice that affirmative action got me into Harvard and Yale. Today they wouldn’t listen.

This skepticism has also been articulated from the august chambers of the Supreme Court. In 2016, Justice Samuel A. Alito Jr. — joined by Chief Justice John G. Roberts Jr. and Justice Clarence Thomas — expressed frustration that those “invoking ‘the educational benefits of diversity’ ” had “not identif[ied] any metric that would allow a court to” evaluate whether the purported benefits were being realized.

But we have found a way to quantify the value of diversity in higher education, as these GOP-appointed justices demanded. In a Columbia Law Review article published this year, we marshaled statistically significant evidence that the value of racial diversity is not illusory.

Our paper, “Assessing Affirmative Action’s Diversity Rationale,” examined the effect of increasing diversity in a setting familiar to the justices: student-edited law journals. The student editors of these publications select and edit the articles they will publish, with a goal of choosing those that will be cited most frequently by legal scholars. Citations are not a perfect measure of an article’s quality, but they are a widely used way to gauge the impact of research in many disciplines and to provide a metric for how well a journal is performing.

Over the past six decades, many leading student-run law journals — including the Yale Law Journal and the Harvard Law Review have taken steps to increase the diversity of their mastheads, believing, like Powell, that a more diverse group of student editors would bring more diverse ideas and experiences to their publications.

What were the effects of this increased diversity on law journals? Drawing upon a database of nearly 13,000 articles published over 60 years, we found that journals that implemented diversity policies saw increases over the subsequent five years of roughly 25 percent in the median number of citations to the articles they published, compared with similar journals that did not implement a diversity policy during the same period. We also found that law reviews with diversity policies did not meaningfully alter the subject matter of the articles they published; they were simply doing a better job of picking the most highly cited scholarship. This increase in the successful selection of articles severely undermines lawsuits contending that diversity policies harm the quality of these publications.

More broadly, our article lends credibility to the idea that diverse student bodies, diverse faculties, diverse teams of attorneys and diverse teams of employees generally can perform better than non-diverse teams. These results, in sum, place empirical heft behind Powell’s much-derided diversity rationale.

The law-review setting is also useful in that it assesses the diversity rationale on its own terms. Some high-profile empirical work criticizes affirmative action by focusing on the outcomes of individual students. But the diversity rationale is not predicated on claims that individual students benefit. It rests on the idea that diversity benefits the institution as a whole — that the learning undertaken and the academic work produced will be stronger if the institutions are diverse.

Our article has generated substantial media attention and was cited in two amicus briefs in the looming cases — one filed by the American Civil Liberties Union and the other by a group of college coaches, headlined by Duke University’s legendary Mike Krzyzewski. As the justices prepare to reconsider affirmative action, we encourage them not to be content with mere unsubstantiated assertions but to examine the empirical reality: Diversity is not the enemy of excellence but its ally.