David Cottrell, Michael C. Herron, Javier M. Rodriguez, and Daniel A. Smith have written this article for American Politics Research. Here is the abstract:

On account of poor living conditions, African Americans in the United States experience disproportionately high rates of mortality and incarceration compared with Whites. This has profoundly diminished the number of voting-eligible African Americans in the country, costing, as of 2010, approximately 3.9 million African American men and women the right to vote and amounting to a national African American disenfranchisement rate of 13.2%. Although many disenfranchised African Americans have been stripped of voting rights by laws targeting felons and ex-felons, the majority are literally “missing” from their communities due to premature death and incarceration. Leveraging variation in gender ratios across the United States, we show that missing African Americans are concentrated in the country’s Southeast and that African American disenfranchisement rates in some legislative districts lie between 20% and 40%. Despite the many successes of the Voting Rights Act and the civil rights movement, high levels of African American disenfranchisement remain a continuing feature of the American polity.