WASHINGTON, Feb. 21 (Xinhua) -- Though the U.S. tax code contains no provision targeting a racial group, the law can actually cause or increase economic disparities between African American households and Whites, CNN reported Monday, citing a recent study.

Research by the Washington D.C.-based Tax Policy Center showed African American couples, on average, face higher tax costs associated with marriage than White people.

"We find that Black couples are more likely than White couples to experience an income tax penalty from marriage and to face higher penalties. We show that these patterns arise because, controlling for income, Black spouses have more equal earning that white spouses ... and because Black couples are more likely to have dependents," researchers said.

The finding, as part of a growing body of research, provides proof of "the likelihood of racial inequities in the tax code," according to CNN.