Objectives: We introduce a new, stable, and reliable measure of gerrymandering based on the number of unnecessary overlapping state House districts within U.S. House districts. We then test for the presence of racial disparities by considering the relative number of unnecessary overlapping districts in majority-white and majority-minority areas. Methods: We utilize a data set encompassing maps in place in the 2012-2022 period from all 35 states with at least four congressional districts. Collectively this includes 386 U.S. House districts and more than 3600 state House districts. Results: We find widespread unnecessary district overlaps. In 34 of the 35 states examined, congressional districts overlap with more state House districts than is mathematically required. Moreover, unnecessary district overlaps are not imposed uniformly. Regression results suggest that districts with the largest white population experience roughly half the unnecessary overlaps imposed on districts with the smallest white population.
Conclusion:We argue the implications of this racial disparity are significant given that previous research finds that confusing district boundaries have a deleterious effect on the basic pillars of representation. This effort represents a new and straightforward gerrymandering metric with implications for the study of representation and the pursuit of fair districts in the courts.This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.