Compulsory voting and political knowledge: Testing a ‘compelled engagement’ hypothesis Jill Sheppard Australian Centre for Applied, Social Research Methods, The Australian National University, Acton ACT 2601, Australia article info Article history: Received 10 May 2015 Received in revised form 6 October 2015 Accepted 7 October 2015 Available online 13 October 2015 Keywords: Compulsory voting Voting Political knowledge Elections abstract Compulsory voting is assumed to have both primary and secondary effects on citizens' political behav- iour. While compulsion increases voter turnout, its effects on political engagement, democratic satis- faction, and electoral advantage are still debated. This study hypothesises that compulsory voting increases citizens’ political knowledge, either because voters choose to become informed given the requirement to vote, or because the process of voting itself imparts incidental knowledge. It also hypothesises that knowledge is distributed more evenly in compulsory systems. Multivariate analysis of data from the Comparative Study of Electoral Systems (Modules 1 to 4) finds some support for the first hypothesis, and stronger evidence in support of the second hypothesis. These findings inform normative debates on the merits of compulsory voting rules. © 2015 Elsevier Ltd. All rights reserved. 1. Introduction Compulsory voting is regularly drawn on to explain political behaviour in countries such as Australia and Belgium (Hooghe and Pelleriaux, 1998; Mackerras and McAllister, 1999), while described as a panacea for political behaviours elsewhere (Lijphart, 1997). This study expands on the existing body of research on both first order (i.e. increasing voter turnout) and second order (i.e. increasing various forms of political engagement beyond the ballot box) effects of compulsory voting. There is overwhelming evidence that compulsion increases turnout (Franklin, 1999; Singh, 2011). Evidence on the relationship between compulsion and non- electoral forms of political engagement is less convincing. This study addresses that gap by testing the relationship between compulsory voting and one of several measures of political engagement: political knowledge. The hypothesis, considered elsewhere but not studied extensively (for example Birch, 2009), is that citizens in countries with compulsory voting demonstrate higher rates of political knowledge. Further, this study hypothesises that knowledge is more evenly distributed in countries with compulsory voting. The positive effects of compulsory voting on political knowledge are contested. From the positive perspective, Lijphart observes that ‘mandatory voting may serve as an incentive to become better informed’ (1997, p. 10). Mackerras and McAllister note that ‘[c] ompulsory voting ensures that voters cast a ballot and the act of voting means that they are forced to think, however superficially, about the major parties’ (1999, p. 229). Compulsory voting not only increases turnout but also reduces differences in socioeconomic status and skill possession among voters and non-voters (Jaitman, 2013; Singh, 2011, 2014). A range of studies have found that compulsory voting increases reliance on party identification heu- ristics (Singh and Thornton, 2013) and leads to greater ‘effective numbers of parliamentary parties’ (Jensen and Spoon, 2011). Other studies have found that compulsion does not increase knowledge or engagement (Loewen et al., 2008), that it decreases non- electoral forms of participation (Lundell, 2012) and that it does only little to reduce stratification between voters and non-voters (Quintelier et al., 2011). This study adds some clarity to the existing debate on the benefits and costs of compulsory voting to political engagement beyond turnout. Applying linear mixed modelling to survey data from the Comparative Study of Electoral Systems (Modules 1 to 4), it examines the distribution of political knowledge across 37 countries. In particular, two key aspects are studied: the possession of political knowledge among citizens of countries with voluntary and compulsory voting, and the relationship between education and political knowledge in countries with voluntary and compul- sory voting. While education is regularly found to predict political knowledge, if compulsory voting does compel engagement as well as turnout, it should follow that education is less important to E-mail address: jill.sheppard@anu.edu.au. Contents lists available at ScienceDirect Electoral Studies journal homepage: www.elsevier.com/locate/electstud http://dx.doi.org/10.1016/j.electstud.2015.10.005 0261-3794/© 2015 Elsevier Ltd. All rights reserved. Electoral Studies 40 (2015) 300e307