Duke University Researchers Develop Nonpartisan Ways to Draw & Evaluate Redistricting Maps

Nov 30, 2016

Earlier this year, a federal court ruled deemed two of North Carolina’s Congressional districts unconstitutional due to racial gerrymandering. That case is to be argued before the U.S. Supreme Court next week. Duke University researchers have developed nonpartisan ways to draw districts and evaluate their fairness.   

After the 2012 elections, mathematics professor Jonathan Mattingly found it puzzling that while Democrats won just over half of the popular vote, they only won 4 out of 13 seats in Congress. So he took the results and applied them to thousands of randomly drawn districts. In the vast majority of cases, he found Democrats winning one to four more seats than they had in the election:

"And so the question is, ‘Is just making sure one person, one vote enough to preserve our democracy?’ And I guess my answer would be no.” 

Mattingly used this mathematical model to evaluate a new map that was drawn by a mock bipartisan redistricting panel and presented to the public in August. Tom Ross of Duke University's Sanford School of Public Policy led that effort. He says North Carolina has very few districts that are truly competitive:

"Politicians don’t really have to be as responsive to the voters during a reelection campaign because their seat is safe, so the voters have a more difficult time holding candidates accountable. They don’t feel that their voice is heard, and they become disengaged."

Mattingly’s model showed the nonpartisan map was far more representational than North Carolina’s current districts. Both researchers say that it’s worth pursuing different ways of drawing and evaluating districts, especially in an age of technology where gerrymandering is becoming more targeted.