How is voting mandatory and what happens if you don't vote? Voting in the US is a right of all legal citizens and we can choose to vote or not. There are many here who refuse to register to vote because they do not want to take the chance they can be called for jury duty. If voting were mandatory here then we would all have to register and it would make it easier for the government locate and control us. We also have a problem with dead people voting and voter fraud, I can't imagine all the problems we would have with 300 million voting.