Tools for using the Advance Group Quarters Summary File

Shapefiles and online databases make it even easier to use the Census Bureau's group quarters data in the redistricting process.

by Peter Wagner, May 17, 2011

Last month, the Census Bureau released the Census Bureau’s Advance Group Quarters Summary File, which for the first time identified which census blocks contain group quarters, such as correctional facilities, early enough that state and local redistricting bodies can choose to use this data to draw fair districts.

The day after the release, we announced a series of tools designed to make this data easier for redistricting professionals and advocates to use. To recap, we’ve made:

1. A point shapefile with the group quarters counts for each block in the country: http://www.prisonersofthecensus.org/data/2010/groupquartersshapefile.html The file contains the number of people in group quarters, and the number of people in different types of group quarters (including correctional facilities). Each blocks that contain a correctional facility includes a URL that links to our database of block annotations.
2. A county-searchable database of census blocks that contain correctional facilities and our annotations. The data is viewable in tabular and Google maps formats at: http://www.prisonersofthecensus.org/locator2010

   For more advanced uses, including preliminary research for Count Question Resolution appeals and determining which blocks should be adjusted prior to redistricting, we’ve made available databases of state, federal, and local correctional facilities and their populations on dates as close to Census day as possible and as well as a memo about new large correctional facilities that were built over the last decade. These resources may be particularly helpful if a block that is of interest to you isn’t yet annotated in our database. These tools are at: http://www.prisonersofthecensus.org/data/

3. Finally, we’ve written two introductions to the data and its uses:
   • Policy-level introduction: Preventing Prison-Based Gerrymandering in Redistricting: What to Watch For, from the Prison Policy Initiative and Demos
   • Technical introduction: Using the Census Bureau’s Advanced Group Quarters Table, from the Prison Policy Initiative

We hope these tools help you draw fairer districts. Don’t hesitate to contact us if you have any questions about these tools.