The U.S. Supreme Court will once again revisit the legality of affirmative action in higher education, after last upholding the decades-old precedent in 2016.
On Monday, the high court said it would take up a pair of cases that challenge the use of race as a factor in undergraduate admissions at Harvard University, the nation's oldest private college, and the University of North Carolina, the nation's oldest public state university.
That the Supreme Court has agreed to hear the cases together is seen by some experts as an indication that the conservative-leaning body could be willing to revisit its precedents and end race-conscious admissions in higher education -- which proponents say will have wide-reaching implications for schools, and beyond.
Some studies suggest the policies -- which consider race as one of many factors when reviewing applicants to further a diverse student body -- have had a profound effect on opportunities for minority applicants, which in turn impact their job chances and careers. And they suggest that stopping them not only decreases the number of Black and Latino students enrolling in colleges but increases those of advantaged groups.
"It is a very, very significant threat to the continued constitutionality of affirmative action," Tanya Washington, a professor of law at Georgia State University whose research focuses on educational equity, told ABC News.
Opponents -- including the conservative group Students for Fair Admissions, which has brought both cases against the universities -- have argued that the policies are discriminatory and violate students' civil rights and the Constitution's guarantee of equal protection.
MORE: Supreme Court takes cases on future of affirmative actionSince 1978, the court has said that race could be used as one factor among many in college admissions, barring the use of quotas or mathematical formulas to diversify a class.
In the landmark 2003 case Grutter vs. Bollinger, which the cases against Harvard and UNC are seeking to overturn, the court said that the goal of a diverse student body justifies the use of race, along with other factors, in admissions policies.
The court set the bar higher for schools with its 2013 decision in the case of Abigail Fisher, a white woman who attempted to end the consideration of race in the University of Texas' admissions policies. In the majority opinion, former Justice Anthony Kennedy said that institutions must first exhaust all race-neutral means of achieving racial diversity, such as recruitment and socio-economic indicators, before considering race, Washington said.
The court last upheld affirmative action in 2016 when it again considered Fisher's case, in a narrow vote that many at the time had expected to upend race-conscious admissions policies.
Since that decision, the makeup of the court has changed in a way that makes it seem likely the precedent could be overturned, according to Washington.
"The court has shifted to a more conservative bloc of justices -- 6 to 3 -- and I think there would be among that group of six a significant receptivity to overruling Grutter v. Bollinger," Washington said, noting that the breakdown is unlikely to change with the retirement of Justice Stephen Breyer.
MORE: Supreme Court Justice Stephen Breyer to retire at end of termWith this latest case, the court could rule in one of several ways, according to Washington. It could say the use of race in admissions violates the 14th Amendment's Equal Protection Clause and overturn Grutter, ending affirmative action. It could uphold Grutter and find that the use of race in Harvard and UNC's admissions policies was constitutional. Or it could uphold Grutter but find that the use of race in these contexts isn't constitutional.
The court could also potentially further restrict the practice or require "higher standards" for schools to use it, Michael Olivas, the emeritus William B. Bates Distinguished Chair in Law at the University of Houston Law Center, told ABC News.
The consolidation of the two cases signals to Washington that "a majority of the court may be ready to overrule Grutter." That the court also appeared inclined to overrule another long-standing precedent in Roe v. Wade also might indicate the same here, she said.
Against the convention wisdom at the time, Olivas had said the court would uphold affirmative action in the 2016 case. He said he believes the same now, even with a different makeup of the court.
"The world has changed, but the common law hasn't changed," he said. "I would hope that 50 years of very clear law would stand."
Should the court end affirmative action in higher education, the impact will be far-reaching, Washington said, as most institutions -- save for those in several states where it is prohibited at public universities -- are using race-conscious admissions policies.
"This is not just going to impact the elite," Washington said. "What we are going to see, what I predict, is a cataclysmic drop in the numbers of Latino, Black and Indigenous students attending institutions of higher ed."
A 2015 study published in the Journal of Higher Education that looked at the impact of affirmative action bans in six states found that the share of students of color in medical schools dropped after the bans went into effect.
In California, which has banned affirmative action policies at the state's public universities since 1996, the education advocacy group EdSource found there was a double-digit enrollment gap between the percentage of Latino high school graduates and those enrolled in the University of California's 2019 freshman class.
If Harvard were to stop considering race in its admissions process and solely use race-neutral factors, the proportion of African American students admitted to the class of 2019 would have likely dropped from 14% to 6%, and the proportion of Hispanic or "other" students from 14% to 9%, a university committee found. Meanwhile, "this decrease would produce a corresponding increase in students of other races, primarily white students," its report said.
Disparities in admissions have implications for those who enter professional fields, like law or medicine, as well as higher education faculty, Washington said.
"I think it will make the quality of education less robust and less rigorous," she said. "I think it will mean we also end up with fewer racially diverse professors and professionals. It's going to have adverse and broad consequences for our society."
For Olivas, one of the worst consequences of potentially ending affirmative action is the message it sends.
"I think it will send a signal to minority parents that their kids aren't wanted," he said. "I think that would be a mistake for all of us. I want a better-educated group no matter where they're from."
Whether or not affirmative action is upheld, disparities in admissions would still exist through policies like legacy admissions, which tend to disproportionately benefit white applicants, he added.
MORE: No more pencils and a shorter test: SAT to go completely digital by 2024In the case against Harvard, Students for Fair Admissions alleges that Asian American applicants have been illegally targeted and rejected at a disproportionately higher rate in violation of the students' constitutional rights. In the case against UNC, it alleges the university refused to use race-neutral alternatives to achieve the stated goal of a diverse study body.
"Every college applicant should be judged as a unique individual, not as some representative of a racial or ethnic group," Edward Blum, the president of Students for Fair Admissions and a long-time affirmative action opponent and conservative activist, said in a statement.
In its complaint against Harvard, Students for Fair Admissions also argued that racial classifications "have a stigmatizing effect" on applicants.
"Irrespective of whether an individual African American or Hispanic applicant is admitted to Harvard because of a racial preference, so long as racial preferences exist, it will often be assumed that race is the reason for the applicant's admission to the school," the complaint stated. "This stigma can have a devastating effect on the psyche of impressionable students."
In response to the Supreme Court's decision this week, both Harvard and UNC said their admissions policies have been found to be constitutional by the lower courts.
"Considering race as one factor among many in admissions decisions produces a more diverse student body which strengthens the learning environment for all," Harvard President Lawrence Bacow said in a statement.
Beth Keith, a spokesperson for UNC, said in a statement that its holistic admissions process "allows for an evaluation of each student in a deliberate and thoughtful way."
Many experts, including Washington, expect the Supreme Court will hear arguments in the case during its next term, which starts in October.