It could be a great way to get greater voter turnout: you have to vote if you're 18 or 16 or whatever the age is. You have to vote. However, I just think there are too many problems inherent in dealing with, for example, “I didn't have a babysitter, so I couldn't come in to vote.”
If it's going to be mandatory, I think you need very clear guidelines in terms of why someone couldn't vote, because as I understand it, there would just be a voters list. If James here didn't vote, we could say we were going to fine him $200 because he didn't come in to vote, and James says, “Well, I didn't have a babysitter.” It's that kind of thing.