Immigrants from around the world are increasingly coming to America. Those patterns have made that perennially unpopular topic — diversity initiatives in higher education— harder to promote at a time when support is flagging.

The education gap between blacks and the broader society has narrowed appreciably, yet still lags at a time when data suggest overall U.S. middle class advancement —and the black middle class in particular—has been stymied by the great recession. In the face of those statistics—and long-held arguments that affirmative action mainly boosts upper middle class blacks—public opinion polls show fairly solid opposition to using race as a university admissions tool.

However, at least one academic argues that changing demographics make the case for more affirmative action.

"When affirmative action started, 99 percent of the blacks in the country were native-born. The assumption was that you'd be helping blacks descendants of slavery and segregation," said Kevin Brown, a law professor at Indiana University's Maurer School of Law and an author of a book that examines the impact of diversity policies on the black community.

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Brown says the influx of non-whites from places such as the Caribbean, Africa and Latin America has complicated the use of preferences in higher education. According to Center for Immigration Studies data, more than 5 million Caribbean and African citizens immigrated to America in 2013.

Brown argues those migration patterns, along with interracial marriages, are distorting the effects of affirmative action. In fact, he says, it's resulting in a crowding-out effect for blacks born domestically, "jumbling up" results on diversity policies, making it difficult to identify who exactly benefits.

"We never really had a conversation about whether blacks [that were not native born] should benefit, or whether multi-racials should be considered black," Brown said. These groups, he claims, "don't have the same connection to history of oppression and racism in the U.S."

Brown stopped short of completely excluding non-American blacks from preferential admissions, adding that potential candidates who are not African-American can explain their connection to historical oppression, or at least state how they'd fight discrimination.

However, Brown says at the current rate, "native blacks will be almost completely cut out."

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