The Consequences of Consequentialist Criteria
The two most significant approaches to redistricting to emerge in the last generation are both consequentialist. That is, they both urge authorities to design — and courts to evaluate — district plans on the basis of the plans’ likely electoral consequences. According to the partisan fairness approach, plans should treat the major parties symmetrically in terms of the conversion of votes to seats. According to the competitiveness approach, districts should be as electorally competitive as is feasible.
Unnoticed by the literature, a substantial number of jurisdictions, in both America and Australia, have heeded these calls from the academy. In sum, consequentialist criteria have been used to shape the district plans for close to three hundred elections over the last four decades. In this paper, I provide an initial assessment of the record of these criteria. The record, for the most part, is mediocre. Controlling for other relevant factors, partisan fairness requirements have not made district plans more symmetric in their treatment of the major parties. Nor have competitiveness requirements made elections more competitive. The likely explanations are the poor drafting, low prioritization, and need for unrealistically accurate electoral forecasts of most consequentialist criteria.
However, other common proposals for redistricting reform — in particular, the use of neutral institutions such as commissions — have performed much better. Elections in Australia, all of which rely on commissions, are much fairer and more competitive than their American counterparts. In the United States, commission usage increases both partisan fairness in state legislative elections and competitiveness in congressional elections, even controlling for an array of other variables. Ironically, it seems that consequentialist criteria cannot achieve their own desired consequences — but that non-consequentialist approaches can.