According to a new publication issued this week by the NAACP Legal Defense and Educational Fund, Inc. (LDF), the increased concern about the mass incarceration of African Americans in the nation’s state and federal prisons has exposed a concomitant insidious practice: prison-based gerrymandering.

The report points out that, when drawing election lines, most state and local governments count prison inmates as residents of the prison communities where they’re incarcerated instead of their true home communities. Because population totals are used to determine the size and shape of election districts and numerous other governmental activities, the false counting practice increases the political influence of the prison districts and weakens that of the inmates’ true places of residence.

Because blacks are about 13 percent of the U.S. population, but make up over 41 percent of federal and state prisoners, prison-based gerrymandering intensifies the negative impact of mass incarceration not just on individual black families but on black communities as a whole, said John Payton, President and Director-Counsel of LDF.

Read the full report.