Combating Gerrymandering with Ranked Choice Voting: An Experimental Analysis of Multimember Districts in the United States

Blunting Gerrymandering with Multimember Districts

How much can election rules blunt the power of partisan mapmakers? In the Operations Research paper “Combating Gerrymandering with Ranked Choice Voting: An Experimental Analysis of Multimember Districts in the United States,” Nikhil Garg, Wes Gurnee, David Rothschild, and David B. Shmoys study this question by combining computational redistricting with models of multiwinner voting. The authors compare single-member districts with multimember districts elected under rules such as single transferable vote (ranked choice voting), using algorithmically generated maps for the U.S. House of Representatives. Their results suggest that even modest three-member districts can help independent commissions reach proportional outcomes, sharply reducing the range of outcomes available to partisan gerrymanderers. The study also tests robustness under voter crossover and explores trade-offs involving geographic cohesion and within-party diversity. The paper points to election-system design as an operations research problem with direct democratic consequences.