The conservative-majority Supreme Court on Monday appeared skeptical of affirmative action in higher education during arguments over race-conscious admissions policies at two prestigious universities.

Over nearly five hours of oral argument, the justices posed sharp questions over admissions programs at the University of North Carolina (UNC) and Harvard University that consider the race of applicants — as one of many criteria — in order to achieve student body diversity.

The court’s majority appeared receptive to arguments by the conservative challengers, Students for Fair Admissions (SFFA), who argued that the schools had impermissibly weighed race in admissions decisions.

“What is your response to the simple argument that college admissions are a zero-sum game?” Justice Samuel Alito asked an attorney for a group of students backing race-conscious admissions. “And if you give a plus to a person who … falls within the category of underrepresented minority but not to somebody else, you’re disadvantaging the latter student?”

The cases heard Monday tee up the prospect that decades of affirmative action precedent could be overturned by the 6-3 conservative majority court, which last court term showed an extraordinary new willingness to scrap past rulings.

A key question heading into Monday’s arguments was how the affirmative action challenge would land with former President Trump’s three nominees — Justices Neil Gorsuch, Brett Kavanaugh and Amy Coney Barrett — none of whom have ruled on the issue as appellate judges. Those justices on Monday appeared to lean in favor of the conservative challengers, though it wasn’t clear how broadly the court’s newest members might be willing to rule.

The court’s three most senior conservatives — Chief Justice John Roberts and Justices Clarence Thomas and Alito — each of whom had opposed racial preferences in prior cases, seemed similarly wary of the colleges’ arguments.

Some of the conservative justices at times seemed to be searching for a way to rule on relatively narrower grounds, for instance by heightening the requirements on schools to explore race-neutral means to reach their diversity goals. Some justices questioned whether eliminating admissions preferences for the children of alumni, donors or other connected applicants might be a step in this direction.

“Suppose the university could achieve, race-neutrally, all of its diversity objectives, if it just eliminated those preferences. Would strict scrutiny require it to do so?” Gorsuch asked, posing a hypothetical question to an attorney representing UNC.

Later, Kavanaugh asked a similar question about whether universities should be required to make these sort of “sacrifices” as part of their pursuit of race-neutral alternatives.

The schools, for their part, contend that that they have explored such approaches — and continue to do so — but that no workable, race-neutral options are available.

The court’s three liberals, for their part, leaned in favor of the schools’ use of race-conscious admissions. Among them was Justice Ketanji Brown Jackson, the nation’s first female African American justice, who participated in the UNC case but recused from the Harvard dispute due to her recent role as a member of Harvard’s board of overseers.

During a colloquy with the lawyer for SFFA, Jackson pushed back against the notion that schools should be allowed to consider a range of applicants’ identity markers — like if they have veteran status or if they are disabled — but not race.

“What I’m worried about is that the rule that you’re advocating, that in the context of a holistic review process, a university can take into account and value all of the other background and personal characteristics of other applicants, but they can’t value race,” she said to lawyer Patrick Strawbridge.

“What I’m worried about is that that seems to me to have the potential of causing more of an equal protection problem than it’s actually solving,” Jackson said, referring to the 14th Amendment’s Equal Protection Clause.

SFFA, in its argument, urged the court to overrule its landmark 2003 decision in Grutter v. Bollinger, which permits colleges to diversify their student populations by using race as one part of a holistic assessment of individual applicants.

The argument highlights a central concern in the cases: the degree to which the use of racial classifications to benefit minorities is compatible with the Equal Protection Clause in the UNC dispute, and with federal civil rights law in the case of Harvard.

SFFA argues that any purported educational benefits that come from student body diversity — a claim which it has called “nebulous” — does not justify breaking with the principle of equal protection.

Lawyers representing UNC and Harvard, student groups and the Biden administration, at turns, emphasized the real-world benefits of racial diversity on campus, from reducing stereotyping to enhancing cross-cultural engagement.

“The evidence and findings in this case confirm what this Court has long recognized: that a university student body comprising a multiplicity of backgrounds, experiences and interests vitally benefits our nation,” lawyer Seth Waxman argued on behalf of Harvard. “Stereotypes are broken down, prejudice is reduced and critical thinking and problem solving skills are improved.”

In its suit against Harvard, SFFA made an additional claim: that the school’s admissions policy discriminates against Asian Americans. The group argued that Harvard’s subjective “personal ratings” scores have tended toward negative racial stereotypes, with the effect of making it harder for Asian Americans to be admitted compared to white applicants.

Waxman at times appeared to struggle with the issue under tough questioning from Alito and Roberts. After Waxman conceded that race is sometimes determinative in admissions decisions, the chief justice pounced.

“Okay, so we’re talking about race as a determining factor in admission to Harvard,” Roberts said.

“Race for some highly qualified applicants can be the determinative factor, just as being an oboe player in a year in which the Harvard-Radcliffe orchestra needs an oboe player will be the tip,” Waxman replied.

“Yeah. We did not fight a civil war about oboe players,” Roberts said. “We did fight a civil war to eliminate racial discrimination, and that’s why it’s a matter of considerable concern. And I think it’s important for you to establish whether or not granting a credit based solely on skin color is based on a stereotype when you say this brings diversity of viewpoint.”

SFFA in both lawsuits suffered defeat in the lower courts, where judges rejected its arguments based on Grutter and related cases, prompting their appeal to the Supreme Court.

Decisions in the cases — SFFA v. UNC and SFFA v. Harvard — are expected by this summer.

Updated at 5:08 p.m.