Evaluating the Effect of Gerrymandering on Partisan Bias in State Legislatures

• In Event: Gerrymandering and Redistricting

Abstract

We identify the effect of gerrymandering across state legislatures in the United States by comparing the current districting plans in state houses to a set of alternative districting plans produced by an unbiased computer algorithm. While this approach is not new, researchers have been limited in their ability to produce realistic maps that not only follow basic districting standards like equal population, contiguity, and compactness but also maintain county boundaries and comply with the Voting Rights Act. This limitation potentially leads researchers to falsely attribute partisan outcomes to gerrymandering when they are in fact an unintended consequence of compliance. To improve upon prior research, we evaluate the effect of gerrymandering using an algorithm that overcomes this limitation.

Authors

• Jowei Chen, University of Michigan

• David Cottrell, University of Georgia