Perhaps the most important point to come out of the Supreme Court’s 7–1 affirmative action decision today is its instruction to lower courts that they may not defer to state college and university representations when deciding whether those institutions have unconstitutionally granted racial preferences in their admissions decisions.

“Strict scrutiny,” the Court said, “does not permit a court to accept a school’s assertion that its admissions process uses race in a permissible way without a court giving close analysis to the evidence of how the process works in practice.” This is a victory for more serious judicial engagement, as Cato urged in the amicus brief we filed in the case.

Justice Anthony Kennedy, writing for the Court, held in Fisher v. Texas that because the Fifth Circuit was more deferential than the Court’s Bakke and Grutter precedents permitted, the grant below of summary judgment for the University of Texas was incorrect. Thus, the Court vacated the decision below and sent the case back for further consideration, based on the more exacting standards of strict scrutiny.

As background for today’s decision, in 1997, in a successful effort to achieve racial and ethnic “diversity” in its student body, Texas instituted a race-neutral “Top Ten Percent Plan” under which any student in the top ten percent of his or her high school graduating class is automatically admitted to all state-funded universities. To fill the remaining slots, the university considered several factors, including race.

In 2008, Abigail Fisher, who is white and was the plaintiff in today’s case, just missed the cut-off for admission to the University of Texas at Austin. She was then denied admission under the alternative admissions program, even though her academic credentials exceeded those of many admitted minority applicants. In our amicus brief supporting her suit, we argued that government may treat people differently because of their race only for the most compelling reasons.

Notwithstanding the text of the Fourteenth Amendment’s Equal Protection Clause, the modern Court has read that restriction as allowing state colleges and universities to consider race as one among several factors to be considered in individualized reviews of each applicant. Ten years ago, in a 5–4 decision in the Grutter case, the Court upheld the University of Michigan Law School’s race-conscious affirmative action admissions process, even though it might favor “underrepresented minority groups,” because the program sought to achieve “class diversity” in a “multi-factored way.” But in a companion case the Court found the university’s undergraduate admissions program unconstitutional because it was more explicit in its use of race to achieve diversity.

That uneasy compromise led many critics to charge that a university could use racial preferences as long as it was clever enough to be vague about what it was doing. That possibility still remains, because the Court did not rule preferences out categorically. Rather, racial classifications are constitutional if “essential”: quoting its opinion in Grutter, the Court today wrote “a university’s ‘educational judgment that such diversity is essential to its educational mission is one to which we defer’” – “an academic judgment to which some, but not complete, judicial deference is proper.” But,

The University must prove that the means chosen by the University to attain diversity are narrowly tailored to that goal. On this point, the University receives no deference. … The reviewing court must ultimately be satisfied that no workable race-neutral alternatives would produce the educational benefits of diversity.

Justices Scalia and Thomas wrote separately. Because Fisher did not ask that Grutter be overruled, they did not urge that here. But they made it clear that in their view the Constitution proscribes government discrimination on the basis of race. Justice Ginsburg dissented from today’s ruling.

On balance, then, this was a qualified win for a color-blind Constitution. It remains to be seen, however, how courts below apply the Supreme Court’s ruling, even in this case, which may yet return to the High Court. The Court’s repeated return to the issue of judicial deference, and the importance of judicial engagement, is perhaps what this decision will most stand for over time. And the implications of that reach far beyond affirmative action.