In an awkward exchange in Wednesday’s potentially game-changing Supreme Court arguments on affirmative action, Justice Antonin Scalia hesitantly asked whether it might be better for black students to go to “a slower-track school where they do well” than to go to a highly selective college, like the University of Texas, through some form of racial preference.

“I — I don’t think it — it — it stands to reason that it’s a good thing for the University of Texas to admit as many blacks as possible,” Scalia said, challenging Gregory G. Garre, the lawyer defending the University of Texas at Austin’s affirmative action policy, which supplements the automatic admission of top-ranking students from all high schools across the state with the use of race as one factor in a “holistic” approach to admissions.

In asking such a pointed question, Scalia was stepping into a long debate over what has been called the mismatch theory of college admissions.

The proponents of the “mismatch effect” say that large racial preferences are harmful to those who receive them, that they learn less than they would if they attended a college more closely matched to their level of academic preparation, receive lower grades, become academically discouraged and socially segregated. Critics say that the “mismatch” research is based on flawed assumptions that cannot be validated by other researchers and that the evidence is more likely to show that all students, regardless of race, benefit from enrolling at the most challenging college that will accept them.

In the current Supreme Court case involving the University of Texas — which could reshape the use of affirmative action in college admissions nationwide — the “mismatch” theory has been well briefed on both sides, although it is not a central argument of either side.

In layman’s terms, some see it as another form of the argument over whether getting a gentleman’s C at Harvard is better for one’s future than getting straight A’s at a lower-ranked university.

“There’s research finding that roughly half of government leaders and half of corporate leaders come from just 12 selective colleges,” Richard Kahlenberg, a senior fellow at the Century Foundation who has studied affirmative action, but favors a class-based admissions process, said Thursday. “So clearly we want to try to find ways to provide access to those institutions for people from a variety of backgrounds.”

But some activists said Scalia seemed to be going beyond the mismatch argument to suggest that African-American students could not compete at top colleges. After his initial comment, Scalia said that “maybe” the university “ought to have fewer” blacks.

“I think Scalia’s comments were both unfortunate and misguided,” said Rachel Kleinman, senior counsel for the NAACP Legal Defense and Educational Fund, which submitted an amicus brief in support of the university on behalf of its Black Student Alliance.

Kleinman said Scalia also might have been disparaging the quality of historically black colleges and universities when he said that “most of the black scientists in this country don’t come from schools like the University of Texas.” Rather, the justice continued, “They come from lesser schools where they do not feel that they’re — that they’re being pushed ahead in — in classes that are too — too fast for them.”

While he was not explicit about what colleges produced the black scientists he was talking about, “A lot of the places they do come from are historically black colleges and universities,” Kleinman said.

Scalia’s comments drew a sharp response from Garre, the university’s lawyer. He said students admitted using their race as one of many criteria “fare better” academically over time than those admitted from the top 10 percent of every high school class, without regard to race.

And in remarks that seemed to allude to the now discredited “separate but equal” doctrine of education, Garre continued, “And frankly I don’t think the solution to the problems with student body diversity can be to set up a system in which not only are minorities going to separate schools, they’re going to inferior schools.”

Stuart Taylor Jr., a Princeton University graduate, lawyer and writer who co-wrote the 2012 book, “Mismatch: How Affirmative Action Hurts Students It’s Intended to Help, and Why Universities Won’t Admit It,” said Scalia’s lack of eloquence had made what he said sound worse than it was.

In the current case, Taylor is counsel on an amicus brief propounding the mismatch theory, on behalf of his co-author on that book, Richard Sander, a professor at the University of California, Los Angeles, law school. “Students who are admitted with far lower grades and test scores and other indicia of academic capability are almost certain to do badly academically, and we think, and this is more debatable, that they’re also likely to do worse in their careers and other departments of life than they would if they were getting good grades at some less prestigious school,” Taylor said.

He said the idea was not to reduce the number of black students going to college, but to admit them to schools where they would be more likely to succeed. “Martin Luther King didn’t go to a fancy college,” he said. “Thurgood Marshall didn’t go to a fancy college. Colin Powell didn’t go to a fancy college.”

Oren Sellstrom, one of the lawyers on a brief attacking the mismatch theory, said that “there is a vast body of social science evidence that shows exactly the opposite of what the mismatch theory purports to show, that actually minority students who benefit from affirmative action get higher grades at the institutions they attend, leave school at lower rates than others, and are generally more satisfied in higher education, and that attendance at a selective institution is associated with higher earnings and higher college completion rates.”

Sellstrom called the mismatch theory “paternalistic,” and said that the concern Scalia’s remarks raised for him was that, “At root he does not believe that students of color belong at elite institutions. I hope that’s not the case, but the tenor of the remarks certainly suggests that that is underlying his thinking.”

Christle Nwora, 21, a senior at the University of Texas and a member of its Black Student Alliance, was admitted because she was in the top 10 percent of students at Plano East Senior High School. She is a humanities major, and in a program that will send her to medical school in the fall. She said prestige had been a factor in her decision to go there.

“I think it goes to the value of my degree,” she said. “It’s one of the most recognizable college brands. We have a strong alumni network, which ranges all across the world.”