Christina Swarns, director of the Criminal Justice Practice for the NAACP Legal Defense and Educational Fund, says the study's findings are part of a larger problem in how the justice system deals with African Americans. "It is obviously part and parcel of the problem of overincarceration of the African-American community in this country," she says. "There is unquestionably ... an association between race and criminality, and I think this study emphasizes how skin color plays an important role in that perception of a link between race and criminality."

William Darity, professor of African-American studies and economics at Duke University and director of the Research Network on Racial & Ethnic Inequality, has studied the impact of skin shade on marriage rates for women and employment for men.

Darity says the Villanova study expands previous research and underscores a known truth. "This has been a long-standing issue and problem that all blacks don't face the same type or degree of discrimination," he says.

Treating people differently because of the lightness or darkness of their skin isn't exclusive to whites. As an example, Darity cites his research, which found that there are "real" disadvantages for darker-skinned black women when it comes to their chances of getting married.

"And one would have to say that's to a large degree the consequence of preferences on the part of black men," he says. That same preference for lighter-skinned black women over darker-skinned black women is true for white men, Darity adds.

But there has been recent movement by the government to take colorism more seriously, Hannon says. He pointed to a 2008 initiative by the U.S. Equal Employment Opportunity Commission that explicitly considers colorism. Hannon also notes that because the Civil Rights Act refers to "color" and not simply race, the door is open for litigation around colorism, which could also push the policy dial.

Darity believes that the benefits of light skin have to be addressed to cause change. "There are clear social and pecuniary benefits to being lighter-skinned in America," Darity says. "Unless we eliminate those benefits, this will go on, because the advantages are real."

Topher Sanders is a newspaper reporter living in Jacksonville, Fla., with his wife and son. You can follow his musings on life, sports and music on Twitter.

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