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Peter Wagner
Executive Director
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How to spot false majority-minority districts in three clicks

by Peter Wagner, October 25, 2012  

Demographers working on voting rights issues frequently examine proposed election districts to ensure that the plans won’t dilute the political power of minority voters. One of the things they look for is the problem of false majority-minority districts.

From the Prison Policy Initiative and Dēmos report, Preventing Prison-Based Gerrymandering In Redistricting: What To Watch For (en español):

Sometimes, a district that seems to have a majority-minority population really doesn’t, because of prison-based gerrymandering. If the minority “population” of the district consists of large number of incarcerated persons – who can’t vote – the district population numbers may be distorted. This creates districts that appear to give minorities the ability to elect the candidate of their choice, but in reality, they cannot. You need to examine any majority-minority district that includes a prison, to ensure that the district really has enough voting-eligible persons of color to create a viable majority with the ability to elect a candidate of choice to office.

Example: In order to settle a Voting Rights Act lawsuit, Somerset County Maryland intended to draw a district where African-Americans could elect a candidate of their choice after the 1990 and 2000 Censuses. But the inclusion of a large prison in the 1st Commission District split the sizable African-American resident voting population between two districts, leaving neither district able to elect a candidate of the African-American community’s choice. While the 1st Commission District appeared to be majority-African-American, in reality the district was not able to function as intended, because many of the purported African-American “residents” of the district were actually behind bars.

screenshot of the detailed demographics page for a particular census blockMost demographers who do this work know how to spot a prison in the population data, but they might not know we developed a very simple way to determine the race and ethnicity of any given incarcerated population in three simple steps:

  1. Go to our Correctional Facility Locator.
  2. Enter the county or state you are interested in the search box.
  3. Find the facility you are interested in by block number. (We’ve likely already annotated it with the name of the facility for you.) Then click on the link marked “detail.

At the bottom of the “detail” page you’ll see a table with race and ethnicity for just the correctional population in that block. We are able to provide this data for every block with a correctional facility in the country except for two in Hawaii and two in New York. For all the others, we provide a unique footnote below the table describing which census tables were used to produce useful race and ethnicity data for the correctional population in that block.

screenshot of an HTMLPopUp showing the detailed demographics page that accompanies the Census Bureau group quarters summary file shapefile
And if you are a GIS user, you can do this in just one click. By using our shapefile, you can access these detail pages right from the info pane of your Maptitude or Arcview software.

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  • September 21, 2016:
    Executive Director Peter Wagner will be speaking at Claremont McKenna College in California. Details TBA.

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