In the 1983 case of Escambia County, Florida v. McMillan et al., the U.S. Supreme Court ruled in favor of a group of African American voters who argued that their county's at-large system for electing commissioners diluted their voting power and violated Section 2 of the Voting Rights Act. The plaintiffs claimed that this method prevented them from having an equal opportunity to participate in the political process and to elect representatives of their choice due to racial polarization in voting patterns. The court agreed with these claims, finding evidence that racially polarized voting was prevalent enough to result in minority vote dilution under an at-large electoral system, thus violating Section 2’s prohibition against practices or procedures which deny or abridge the right to vote on account of race or color.

In the dissenting opinion for Escambia County, Florida, et al. v. McMillan et al., Justice Thurgood Marshall argued that the majority's decision failed to consider the historical context of racial discrimination in voting practices within Escambia County. He pointed out that while there may not be explicit discriminatory intent in their current at-large electoral system, it was originally established with a racially discriminatory purpose and continues to have a disparate impact on black voters. Therefore, he believed this should constitute a violation of Section 2 of the Voting Rights Act as it results in unequal access to political process for minority voters. Furthermore, he disagreed with the majority's interpretation of legislative history and congressional intent behind amendments made to Section 2 in 1982; arguing they were designed specifically to address such situations where electoral systems disproportionately disadvantage minority groups even without clear evidence of intentional discrimination.