Sunlight Foundation’s OpenGov Voices: Creating congressional district maps with Mapbox

Every 10 years — after the decennial census and as mandated by the U.S. Constitution – states are subdivided into sets of congressional districts for representation in the U.S. House of Representatives. GovTrack provides maps of these congressional boundaries for your reference and makes the maps available for embedding on other sites.

Beyond looking up the district for a specific address, maps introduce a geographic context that tells us about the demographics and rural/urban nature of a district and any signs of gerrymandering, as well as whether that district's boundaries show signs of gerrymandering. Continue…