It depends on whether or not a person’s conscience has been rightly formed. If someone is refusing to vote because he has studied the candidates on the ballot for a particular office and cannot in conscience vote for any of them, that is his prerogative. He should still vote for other offices where there is an acceptable candidate and on the various measures and propositions presented for a vote. But if someone is refusing to vote at all because he doesn’t believe he should vote in general, then his conscience may be improperly formed. The Catechism of the Catholic Church states: “Submission to authority and co-responsibility for the common good make it morally obligatory to pay taxes, to exercise the right to vote, and to defend one’s country” (CCC 2240).