Non-voting

Abstention is a term in election procedure for when a participant in a vote either does not go to vote (on election day) or, in parliamentary procedure, is present during the vote, but does not cast a ballot. Abstention must be contrasted with "blank vote", in which a voter casts a ballot willfully made invalid by marking it wrongly or by not marking anything at all. A "blank (or white) voter" has voted, although their vote may be considered a spoilt vote, depending on each legislation, while an abstaining voter hasn't voted. Both forms (abstention and blank vote) may or may not, depending on the circumstances, be considered to be a protest vote (also known as a "blank vote" or "white vote").

An abstention may be used to indicate the voting individual's ambivalence about the measure, or mild disapproval that does not rise to the level of active opposition. Abstention can also be used when someone has a certain position about an issue, but since the popular sentiment supports the opposite, it might not be politically expedient to vote according to his or her conscience. A person may also abstain when they do not feel adequately informed about the issue at hand, or has not participated in relevant discussion. In parliamentary procedure, a member may be required to abstain in the case of a real or perceived conflict of interest.

Abstentions do not count in tallying the vote negatively or positively; when members abstain, they are in effect attending only to contribute to a quorum. White votes, however, may be counted in the total of votes, depending on the legislation.

An active abstention can occur where a voter votes in a way that balances out their vote as if they had never voted. This has occurred many times in the House of Commons of the United Kingdom. During a division (a process where a yes/no vote occurs to agree or disagree to a motion), a Member of Parliament may actively abstain by voting both "yes" and "no". This is effectively the same as not voting at all, as the outcome will not be changed by the active abstention. However, in the House of Lords of the United Kingdom, active abstention is not possible as a Lord voting both ways will be removed from the list of votes.

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