When I was younger, I was against compulsory voting. I thought people should be free to spend their time as the wish and to not participate in politics if they wished. My view has changed.
A compelling justification of the state is that it exists to solve collective action problems. Externalities. Public Goods. Other cases where markets/distributed action fails and we need some kind of central enforcement. I think voting is a collective action problem.
For voting to be a collective action problem, the individually rational action must lead to collectively irrational outcomes. Individually, choosing not to vote is often rational as voting requires giving up hours of time for virtually zero benefit[^1 ] as the chance of a single vote swinging the result is miniscule. Collectively, we want a government which gives every individuals preferences equal weight. Systemic non-voting means this is not the case. In theory if only a small proportion of citizens voted but that group was representative of the population there would be no harm. In reality propensity to vote is not random and the voting population is systematically different from the non-voting population. In the west today
- The politically extreme are more likely to vote than moderates.
- Those with a lot of free time, e.g: pensioners, are more likely to vote than those without much free time.
- The poor are less likely to vote than the better off. (Probably partly cultural, partly economic[^2])
Voluntary voting leads to inequality in representation as certain groups collectively matter less than others. If political factions know that group X votes with probability 0.8% and group Y with 0.4%, they will care twice as much per person for satisfying/converting members of X as members of Y. Hence the rational individual choice to not vote when done at scale leads to the unwanted collective outcome of unrepresentative government. Assuming most people would prefer to give up a few hours of their time to make government more representative, this is a collective action problem. It also has serious ramifications for society. Hence I tend to lean towards government intervention being justified. Hence compulsory voting.
[^1 ]: There are exceptions here. e.gL if you live in a swing state in a first past the post system etc… For now I’ll leave those aside
[^2]: Yes there are laws preventing employers from punishing people who take a few hours off to vote. No those laws are no enforced.