Partisan Gerrymandering and Turnout

How does partisan gerrymandering affect turnout for US House elections? Common measures of gerrymandering are a function of turnout, which makes assessments of the impacts on turnout difficult. We present evidence from two natural experiments. First, using a nationwide sample, we construct a state-level measure of gerrymandering based on the partisan composition of districts and leverage variation stemming from congressional redistricting. Second, we draw on Pennsylvania and Ohio voter files and leverage the court-ordered redrawing of Pennsylvania districts in 2018 aimed at undoing partisan gerrymandering. Both approaches reveal that higher levels of partisan gerrymandering causally reduce turnout.