The Minimal Effects of Union Membership on Political Attitudes

Abstract

Union membership has long been believed to liberalize a range of political attitudes from partisanship to racial prejudice. This paper argues that the theoretical preconditions necessary for such influence are unlikely to hold. Union members may not receive, may ignore, and may deprioritize their union's message compared to other considerations. Previous research faced empirical challenges with causal inference, limited sample sizes, and limited outcomes. My analysis is the first to bring together all of the publicly available panel data. I analyze 13 panel surveys from 1956 to 2020 with 37,621 respondents using difference-in-differences designs to evaluate whether union membership causes political, economic, and social attitudes to liberalize across 57 outcomes. I find that gaining union membership has less meaningful short-term, medium-term, and long-term persuasive effects than previously believed. These results suggest a reconsideration of the role of labor unions in political behavior.

Keywords: labor unions, political behavior, American politics