Voting rates in many contemporary democracies are (according to many observers) low, and seem in general to be falling. The United States, for instance, barely manages about 60% in presidential elections and 45% in other elections (Brennan and Hill 2014: 3). Many other countries have similarly low rates. Some democratic theorists, politicians, and others think this is problematic, and advocate compulsory voting as a solution. In a compulsory voting regime, citizens are required to vote by law; if they fail to vote without a valid excuse, they incur some sort of penalty.
One major argument for compulsory voting is what we might call the Demographic or Representativeness Argument (Lijphart 1997; Engelen 2007; Galston 2011; Hill in J. Brennan and Hill 2014: 154–173). The argument begins by noting that in voluntary voting regimes, citizens who choose to vote are systematically different from those who choose to abstain. The rich are more likely to vote than the poor. The old are more likely to vote than the young. Men are more likely to vote than women. In many countries, ethnic minorities are less likely to vote than ethnic majorities. More highly educated people are more likely to vote than less highly educated people. Married people are more likely to vote than non-married people. Political partisans are more likely to vote than true independents (Leighley and Nagler 1992; Evans 2003: 152–6). In short, under voluntary voting, the electorate—the citizens who actually choose to vote—are not fully representative of the public at large. The Demographic Argument holds that since politicians tend to give voters what they want, in a voluntary voting regime, politicians will tend to advance the interests of advantaged citizens (who vote disproportionately) over the disadvantaged (who tend not to vote). Compulsory voting would tend to ensure that the disadvantaged vote in higher numbers, and would thus tend to ensure that everyone’s interests are properly represented.
Relatedly, one might argue compulsory voting helps citizens overcome an “assurance problem” (Hill 2006). The thought here is that an individual voter realizes her individual vote has little significance. What’s important is that enough other voters like her vote. However, she cannot easily coordinate with other voters and ensure they will vote with her. Compulsory voting solves this problem. For this reason, Lisa Hill (2006: 214–15) concludes, “Rather than perceiving the compulsion as yet another unwelcome form of state coercion, compulsory voting may be better understood as a coordination necessity in mass societies of individual strangers unable to communicate and coordinate their preferences.”
Whether the Demographic Argument succeeds or not depends on a few assumptions about voter and politician behavior. First, political scientists overwhelmingly find that voters do not vote their self-interest, but instead vote for what they perceive to be the national interest. (See the dozens of papers cited at Brennan and Hill 2014: 38–9n28.) Second, it might turn out that disadvantaged citizens are not informed enough to vote in ways that promote their interests—they might not have sufficient social scientific knowledge to know which candidates or political parties will help them (Delli Carpini and Keeter 1996; Caplan 2007; Somin 2013). Third, it may be that even in a compulsory voting regime, politicians can get away with ignoring the policy preferences of most voters (Gilens 2012; Bartels 2010).
In fact, contrary to many theorists’ expectations, it appears that compulsory voting has no significant effect on individual political knowledge (that is, it does not induce ignorant voters to become better informed), individual political conversation and persuasion, individual propensity to contact politicians, the propensity to work with others to address concerns, participation in campaign activities, the likelihood of being contacted by a party or politician, the quality of representation, electoral integrity, the proportion of female members of parliament, support for small or third parties, support for the left, or support for the far right (Birch 2009; Highton and Wolfinger 2001). Political scientists have also been unable to demonstrate that compulsory voting leads to more egalitarian or left-leaning policy outcomes. The empirical literature so far shows that compulsory voting gets citizens to vote, but it’s not clear it does much else.