[jacques_chester]

Many people feel that compulsory voting is immoral.

However, insofar as the legitimacy of the system of government depends on the franchise, it follows that a more thorough exercise of the franchise increases the legitimacy of the outcome[1].

There are however perfectly practical reasons to have compulsory voting. The biggest is that it dampens oscillations and creates pressure on the whole political system to focus on the median voter.

If you gave me a dictatorial remit to reform the US electoral system, compulsory voting would be one of the policy options I would choose. The others would be instant runoff voting, possibly the abolishment of the electoral college, holding elections on a Saturday and creating an independent electoral commission.

[1] Sophistry, of course. You can counter-argue that only willing exercise of the franchise grants legitimacy. But of course, it is economically irrational for any voter to turn out; just as it is irrational to pay taxes voluntarily. For any such system to work, compulsion is a necessity. You cannot make it go away, only decide where it is most required.