Supreme Court Justice Lewis Powell was the deciding vote in the case Regents v. Bakke.Anonymous / AP

Supreme Court Justice Lewis Powell was on the fence in 1978. The Court had before it the case of a 35-year-old white man, Allan Bakke, who had twice been denied admission to the medical school at the University of California at Davis. Bakke claimed that he was unfairly rejected because of the school’s quota system, which reserved 16 seats in the 100-person class for minority students. Powell didn’t know it at the time, but his decision would come to shape the affirmative-action debate for the next 40 years.

Powell’s opinion would buoy the case for affirmative action in college admissions, but some legal scholars argue that it also transformed the conversation about race and equality in America by altering the meaning of one of the Civil War amendments to the Constitution aimed at ensuring equality for recently freed slaves. As Kevin Brown, a law professor at Indiana University, told me, “Powell’s opinion in [Regents of the University of California v.] Bakke becomes the opinion that amounts to the change in the definition of the Equal Protection Clause.” And by shifting its meaning, he says, Justice Powell inadvertently changed how colleges go about recruiting and enrolling racial minorities. That shift may prove consequential as the use of race-conscious admissions at Harvard University goes on trial starting Monday.

The Equal Protection Clause is a short but critical line in the Fourteenth Amendment that states that Americans in similar circumstances should be treated equally under the law. And it’s what Bakke’s case hinged upon. He argued that the quota system at UC Davis infringed upon his Fourteenth Amendment rights and that the university was in violation of Title VI of the Civil Rights Act of 1964, which bars institutions that receive federal funds from discriminating on the basis of race—a lower hurdle toward receiving a favorable ruling than his Fourteenth Amendment argument.

The case had divided the Court: Four justices agreed with Bakke that the university’s affirmative-action strategy violated Title VI because it put a cap on the number of white students who could get in. (Those justices did not take up the Fourteenth Amendment question.) And four other justices argued that the college’s quota system was permissible under both Title VI and the Fourteenth Amendment.

“I suspect that it would be impossible to arrange an affirmative action program in a racially neutral way and have it successful,” Justice Harry Blackmun, one of the supporters of the UC Davis quota system, wrote. “To ask that this be so is to demand the impossible. In order to get beyond racism, we must first take account of race. There is no other way. And in order to treat some persons equally, we must treat them differently.”

That 4–4 split left Justice Powell as the deciding opinion. “Powell’s opinion sort of split it down the middle,” Brown told me. “He concluded that you could use race as a factor in admissions, but that you could not use quotas. And he went on to say that the only justification for affirmative action was the educational benefits of having a diverse student body.” Race, Justice Powell opined, could only be used in coordination with other factors for the purposes of diversity. As Powell put it, “There is a measure of inequity in forcing innocent persons in [Bakke’s] position to bear the burdens of redressing grievances not of their making.”

Powell’s jurisprudence upended the dominant view at the time, Brown says, that the Equal Protection Clause was aimed at helping “discrete and insular minority groups,” including African Americans, Asians, and Latinos. What that means is that “when you applied the Fourteenth Amendment, it should come to a different result if blacks, for example, were going to be the beneficiaries, as opposed to the ones who were disadvantaged,” Brown says.

Still, Justice Powell’s opinion that these institutions could consider race in admissions, but only for purposes of diversity, took hold. But that justification of affirmative action flew smack in the face of the spirit of the practice, Natasha Warikoo, an associate professor of education at Harvard, told me. “Many of these universities had systematically excluded African Americans. And even if they hadn’t officially excluded African Americans, their policies really made them inaccessible to most African Americans,” she says. Affirmative-action policies “were a way to sort of acknowledge that past and to try to be leaders in the movement toward social justice and racial justice in the United States.”

Without the extra push of a rationale rooted in remedying discrimination, minority enrollments stagnated. According to The New York Times, the percentage of black freshmen at elite schools has remained “virtually unchanged” since 1980. “Black students are just 6 percent of freshmen but 15 percent of college-age Americans,” the Times reported.

Since the Bakke case, the court has, time after time, upheld race-based affirmative action as permissible, but the precedent set by Justice Powell’s decision that the Fourteenth Amendment is based on individual rights, regardless of race, provided the window to weaken the practice, Brown told me. Forty years later, the effects of that decision are still being felt on college campuses.

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