Redistricting and partisan fluidity: do we really know a gerrymander when we see one?

Redistricting analysis and the concept of gerrymandering are based on the assumption that the electorate is comprised of durable racial, ethnic or partisan blocs of voters. Accordingly, vote dilution analysis is employed to determine whether the constituencies comprised of these durable blocs have had their aggregate voting power diminished by a particular redistricting scheme. In this article, I demonstrate that this assumption does not hold for partisan redistricting analysis because partisan blocs of voters are not durable. Instead, their partisan profile changes in response to incumbency, electoral competition and redistricting. These findings not only contradict prevailing analyses of redistricting, but also undermine the logic of remedial redistricting.