From Gridlock to Polarisation?

Abstract

We propose a mechanism linking legislative gridlock to voters’ support for candidates who hold extreme policy positions: voters rationally discount policy proposals on gridlocked policy issues because on these issues policy change is unlikely. When voters have preferences that are moderate and broadly aligned with a single party across policy issues, gridlock increases support for extreme co-partisan candidates. We test our mechanism in a large-scale online experiment in which we randomly vary subjects’ perceptions of gridlock and measure subjects’ support for candidates in candidate-choice tasks. We verify that greater perception of gridlock on a specific issue increases moderate, self-identified partisan subjects’ propensity to vote for extreme co-partisan candidates on the gridlocked issue. We show that our experimental evidence is consistent with our mechanism and that other mechanisms are less likely to underlie our main result. We discuss and analyse additional predictions of our mechanism, including a possibly moderating effect of gridlock that occurs when voters have preferences that are extreme and do not align with a single party across issues. Our theory offers a possible causal connection from gridlock to elite polarisation that may inform further empirical work and suggests a novel tradeoff between elite polarisation and policy stability in constitutional design.