Democracy in Unequal Times: How Economic Inequality Influences Voter Turnout, Party Polarization, and Union Density

This thesis proposes three studies to explore the impact of income inequality on established democracies. The aim of this thesis is twofold: (1) to investigate the political sustainability of large income gaps; and (2) to understand why inequality increased in democracies. The first paper analyzes the behavior of political elites. Scholars of US politics report a strong connection between inequality and party polarization. Evaluating this relationship comparatively, I instead find that inequality depolarizes parties’ economic positions. This happens because inequality depresses low-income voters’ participation. This changes the composition of the core constituencies on the left, leaving redistributive positions with less support. The left moderates, while the right stays put. This leads to convergence on economic issues. The second paper then evaluates why the US is different. Since participation links inequality to party convergence comparatively, I investigate the effect of income gaps on turnout in American states. Previous research on this relationship shows contrasting evidence for the American case: some scholars report a negative impact; others a null effect; and some even a positive one. Differently, I suggest that the relationship is curvilinear: moderate inequality increases turnout; while very low or very high gaps reduce it. An analysis of turnout in American states from 1980 to 2010 finds supporting evidence for this prediction. The third paper then focuses on the effect of inequality on behaviors beyond voting. The study is the first to systematically analyze the implications of inequality for unionization levels in democracies. Contrary to intuition, I argue that inequality reduces union density: in unequal times, workers lose confidence in unions. This increases the risk of de-unionization over time. Studying both individual survey data and panels for the aggregate level, I find that inequality reduces union density in advanced democracies.