Geographic Gerrymandering

The leading measures of gerrymandering reflect a party-centric theory of representation based on the statewide relationship between seats and votes. But electoral districting, a traditional practice that still predominates, reflects a geographic theory of representation focused on the district-based relationship between a representative and her constituents. We propose a new approach to gerrymandering that takes electoral districting on its own terms and defines fairness geographically without reference to the seats-votes relationship. Scholars, courts, and mapmakers recognize the representational interests advanced by geographic criteria, such as preservation of local political boundaries. We ask whether an electoral map fairly distributes these benefits. Under this approach, “geographic gerrymandering” occurs when a map unjustifiably distributes geographic impacts on the basis of race or party. This approach offers new methodological and conceptual possibilities, and a new way for courts to adjudicate gerrymandering claims that may avoid the justiciability problems the Supreme Court identified in Rucho v. Common Cause. To demonstrate this approach in action, we analyze unnecessary county splits in congressional maps of the thirty-five states with four or more representatives. Overall, mapmakers differentially impose the burden of county splits on Black residents and Democrats. But the effect depends on who draws the lines. When a neutral actor draws the lines, the disparities disappear. When Democrats draw the lines, Black residents are slightly favored but Democrats are disfavored. When Republicans draw the lines, both Black residents and Democrats are significantly disfavored. And when both parties draw the lines, both Black residents and Democrats are disfavored even more. These results demonstrate the value of a geographic approach and suggest further research