The causal effect of compulsory voting laws on turnout: Does skill matter?

A very important, yet unsettled, question is whether mandatory voting affects political participation. This paper exploits a natural experiment to assess the causal impact of compulsory voting on turnout and, more importantly, to test whether the impact is different across skill groups. I find that compulsory voting increases voter turnout by 18 percentage points (28%) and the increase is twice as much in the unskilled citizens than that in the skilled citizens. This study is the first to show, with rigorous empirical evidence, that compulsory voting laws are effective in reducing the skill/socioeconomic gap in political participation. Furthermore, by shaping the electorate, these laws have relevant consequences in terms of the economic policies applied.