The next time President
For some people, not voting is a purposeful and informed decision that they feel sends a message about their disgust with the candidates who are running or the political process itself. It's not a decision I particularly agree with — there's not much evidence that terribly low voter turnout has improved politics or the quality of the people who run for office — but it's theirs to make.
The president cites Australia as an example of a country with mandatory voting, but Australia does not have the explicit guarantee of free speech that is embedded in the U.S. Constitution.
Mandatory voting also would interfere with the right to privacy. Voter registration records are public — including the voter's address. Admittedly, the Internet has made true privacy a rare thing, but there are people who guard this kind of information carefully. The government shouldn't be trying to force them into making their lives any more open to the public than they want.
And what about people who generally vote but for one reason or another feel that they're not ready to participate in one particular election or another? They might be overwhelmed by an illness or death in the family or other extraordinary events and unable to muster the interest in learning about the candidates and issues on the ballot. It doesn't necessarily make someone a bad or uncaring citizen to sit out an election.
Of course, it's a secret ballot; they and anyone else forced to vote could go to the polls and simply decide not to vote for anything once they get there. But they shouldn't have to — and besides, once there in the booth, confronted with a ballot, people tend to want to fill in the blanks, even if they're not remotely informed about what's on there. Unwilling voters do not make for better democracy.
Even when it comes to the pragmatic arguments the president raises — especially the possibility of reducing the role of big money in elections — mandatory voting is more likely to backfire than improve the democratic process. It will take a lot more money to reach all those voters, for bigger phone banks, more paid people to knock on doors, extensive advertising. More need for campaign contributions, more opportunities for big money to shape elections and politicians who are ever more a product of that money machine.
Obama's idea should have stayed quietly in his mind until he had a chance to think it through and realize that although it would definitely increase the number of people who vote, that's not the same thing as greater participation in elections. Not to mention that it's almost certainly unconstitutional.