PR/STV Voting System Frequently Asked Questions

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PR (Proportional Representation) is an electoral system designed to make sure that the candidates elected represent accurately the opinions of the voters, i.e. that the strength of each party in the elected forum is in proportion to its support among the people. The system used in Northern Ireland is called the Single Transferable Vote, STV for short. Every voter has only one vote, but they can ask for it to be transferred from one candidate to another to make sure it is not wasted. This is done by numbering the candidates 1, 2, 3, 4, 5 and so on instead of just putting an "X" against one of them.

In a single-member constituency, where the "X" vote system is used, all the votes not cast for the winning candidate are wasted, since they have not been able to elect anyone. And so are all the votes in excess of a bare majority cast for the winner, in the sense that they have had no effect on the result.

If the strength of one party was consistent in every constituency, no opposition candidates could ever be elected. The single-seat majority-vote system works only because parties are stronger in some areas than others, and this is why there is so much difficulty in fixing constituency boundaries.

With PR several candidates are elected together, representing all the sizable bodies of opinion in the constituency, in proportion to their strength. The bigger the constituency, the more chance a small party has of electing a representative. In a 7 seat constituency, for instance, any candidate who gets more than 12.5% of the votes will be elected. (See the Quota FAQ)

One way of visualising a PR election is to think of how a class of children might choose 3 prefects. A number of candidates stand at the front of the room and the children line up behind their favourites. At first the most popular candidate has most of the children behind him, and the least popular only a few. The children at the end of the longest line see their favourite does not need their support, and move behind their second choice; the ones behind the least popular candidate see he has no chance, and they also move behind their second choice.

Finally all the children are ranged in more or less equal numbers behind just 3 of the candidates. Every child has had a part to play in the election, and has seen that their vote counts, even though some of them may not have got exactly what they first wanted.

The quota is the number of votes a candidate needs to be elected. People often assume for example that if there are 5 candidates to be elected, the quota must be one-fifth of the total valid votes cast. In fact in this case the quota is one-sixth of the total valid votes cast, plus one vote, and it is clear that this must be so if we think what the quota would be in a single-seat constituency.

To be sure of being elected a candidate needs only one more than half the total valid votes. Similarly in a 2-seat constituency a candidate needs only one-third of the total valid votes plus one to be sure of being elected. In a 3-seater, one-fourth plus one, and so on. In other words, to find the quota you simply divide the total valid votes by one more than the number of seats to be filled, and add one vote to the result.

First there is a verification stage. This is where the ballot papers are counted and checked against the number of votes recorded in the Ballot Paper Account for each polling station. The votes are then sorted according to the first preferences of the voters. That is, each candidate is allocated every ballot paper on which there is a 1 against their name. It is at this point that invalid ballot papers are adjudicated, the total number of valid votes counted and the quota worked out. Any candidate who is then found to have reached the quota of votes is elected.

Some candidates may then have a surplus over the quota. Others may have so few votes that they can be eliminated from the contest. The remaining stages of the count are concerned with the transfer of surpluses or the elimination of candidates with the least number of votes.

When there are no more preferences expressed on a ballot paper it is retired from the count as "non-transferable" and those ballot papers cease to have any further influence on the result.

A statement will be published showing exactly what happened at each stage of the count. It will show the number of "first preference" votes for each candidate and the number of votes transferred to each of them when a surplus is distributed from a candidate who has reached the quota or when a candidate is eliminated. It will also show the number of papers which at each stage become "non-transferable" because the voters had not expressed enough preferences or because their preferred candidates have been eliminated.

The voter will therefore be able to follow the progress of their vote through the count and see how it is working to affect the final result.

Yes. When a candidate is eliminated, for instance, their ballot papers are taken and added to the piles of the candidates still in the running, in accordance with the voters' preferences. Ballot papers which show no further preferences, or preferences only for candidates already eliminated, are put aside as "non-transferable".

Suppose the quota is 1,000 votes and candidate "A" gets 1,500 votes in the first count. That means 500 of their votes, a third of the total, are to be re-distributed as surplus.

Instead of transferring one third of the votes, all the 1,500 votes are transferred at one third of their value. This does not mean that your vote is actually divided up. It is simply a mathematical way of ensuring that the value of 500 votes is transferred to the candidates to whom they are due in the proper proportion. This explains why there will be fractions of votes shown in the results of various counts.

Each voter has only one vote, so strictly speaking the question should be, "How many alternative preferences can I express?" The answer is that you can number as few or as many candidates as you like. As long as the number 1 is put opposite the name of one candidate your vote is valid. But you can place a number to indicate your order of preference against every candidate on the ballot paper, no matter how many seats there are to be filled.

This means voting for only one candidate, or restricting your preferences to the candidates of only one party.

No. Your vote can only be transferred when your first choice or choices do not need it or cannot use it, i.e. after they are elected or eliminated. So you do not help your favourites by ceasing to indicate preferences after you have voted for them. If among the remainder of the candidates there are some you would like more than others, or dislike less, you should express preferences for them and thereby influence the election right to the end.

You should study the lists of candidates (in the newspapers or the election literature) well beforehand and make up your mind about your preferences among the candidates and parties. There will probably be quite a number of names on the ballot paper. They will be in alphabetical order, and the parties they belong to will be shown, as well as each party's official logo.

When you get your ballot paper, mark the number "1" against the name of the candidate you most wish to see elected (the space is on the left hand side of the ballot paper).

Then ask yourself, if you cannot have your favourite or if he doesn't need your vote, which other candidate you would like to see elected; put a 2 against their name. Then a 3 for your third choice, 4 for your fourth choice, and so on.

You must careful not to put the same number against more than one candidate, or to miss out a number. If you should do so those preferences, and any later ones you mark, will not be counted. If you do make a mistake when you are filling out your ballot paper, bring it back to the Presiding Officer and ask for another one.