Skip Navigation
Expert Brief

The Curious Case of North Carolina’s Congressional Map

Who draws the maps seems to drive partisan bias in North Carolina’s congressional maps more so than political geography.

Published: August 24, 2017

It some­times gets argued that geographic clus­ter­ing of Demo­crats in cities is respons­ible for the fact that Repub­lic­ans have an advant­age when it comes time to draw congres­sional and legis­lat­ive maps. That argu­ment certainly has been made in North Caro­lina, where the state has been mired in a decade long fight over alleg­a­tions of racial and now partisan gerry­man­der­ing.

But the claim that clus­ter­ing rather than polit­ics is giving North Caro­lina a Repub­lican tilt turns out to rest on some pretty dubi­ous premises. That’s because the high rate of partisan bias seen in this decade’s North Caro­lina map is a new phenomenon. And it coin­cides not with any sudden and unex­pec­ted migra­tion of Demo­crats into cities after 2010 but rather with a change in the party that had control of the redis­trict­ing process. Up until 2011, Repub­lic­ans in North Caro­lina had never had sole control of the redis­trict­ing process. That changed in 2011, and the differ­ence between North Caro­lin­a’s pre-2011 maps and the one drawn by the new Repub­lican major­ity could not be more stark.

In short, if you are look­ing for why maps in North Caro­lina and six other single-party controlled states are biased, start with who drew the map.