The gerrymandering of educational boundaries and the segregation of American schools : a geospatial analysis

Despite steady and substantial decreases in residential racial/ethnic segregation since the 1960s, public school segregation is increasing steadily. As a result of these trends, schools, which have historically been less segregated than their surrounding neighborhoods, are now becoming more segregated than neighborhoods, underscoring the need for research on the ways in which educational institutions are facilitating segregation. Adopting a “student exchange” framework from the literature on electoral gerrymandering, this study provides initial empirical evidence examining how gerrymandered educational boundaries exacerbate or ameliorate patterns of residential segregation by “zoning in” certain students and “zoning out” others. Using a large, nationally-representative sample of 9,717 school attendance zones and 9,796 school districts, this study employs geospatial analytic techniques to investigate the effects of school attendance zone and school district gerrymandering on the racial/ethnic diversity of schools and districts. The effect of gerrymandering on diversity is assessed by comparing the characteristics of students residing in current boundaries to those residing in the “natural”, compact zone or district that would be expected in the absence of gerrymandering, operationalized as the equal land area circle of Angel and Parent (2011) and convex Voronoi polygons. Analyses reveal that, on average, both school attendance zones and school districts are gerrymandered to “zone out” more racially/ethnically dissimilar students in favor of more racially/ethnically similar students. As a result, schools and districts are significantly more racially and ethnically homogeneous than they would be in the absence of gerrymandering. While gerrymandering serves to segregate students of all races and ethnicities, it particularly serves to exclude blacks and Hispanics from predominantly white schools and districts, reinforcing the historical divisions between these groups. Indeed, estimates suggest that, on average, school attendance zones and school districts are 15% and 14% less black-white diverse, respectively, than would be expected if their boundaries were not gerrymandered. Findings suggest that the gerrymandering of boundaries adds another pernicious layer of segregation to public education institutions, which are already highly segregated by residency. The finding that the gerrymandering of school attendance zones and school districts serves to segregate underscores the importance of educational boundaries as a contemporary mechanism of segregation. However, findings also warrant some optimism. Because attendance zone and district boundaries are modifiable and subject to policy intervention, state standards for boundary compactness and rezoning efforts designed to create more equitable boundaries present cost-effective opportunities to achieve meaningful gains in integration. While changing school district boundaries is less politically feasible than changing school attendance zones, when such windows of opportunity arise, they have the potential to reduce school finance inequities and equalize educational opportunity while also increasing racial/ethnic equity.