Since the foundation of the State, Ireland has used the electoral system known as proportional representation with a single transferable vote (PR–STV, or PR for short).
This means at local, mayoral, national, general and presidential elections, voters are asked to give their vote in order of preference.
Referendums, in which people are asked to vote on changes to the Irish Constitution, operate on a ‘Yes’ or ‘No’ basis.
Voters can stop after indicating their first choice candidate, or can continue to give a preferential vote to as many candidates as they wish on the ballot paper.
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When you vote with more than one preference, you are instructing the returning officer – the person responsible for the counting of votes – that if your preferred candidate is eliminated, or elected with a surplus of votes, you want your vote to be transferred to your second choice candidate.
Lower preferences come into play only when higher ones are elected or eliminated.
In Dáil and European election constituencies, the number of seats (or elected representatives) can be 3, 4 or 5 per area, depending on population size.
In local elections, constituencies are called Local Electoral Areas (LEAs), and the number of seats in these can vary between 3 and 7.
When it comes to counting votes, ballot papers are sorted into first preference choices for each candidate and then the first preferences are counted.
The total valid poll is determined after all spoilt votes have been adjudicated on. Ballot papers may be deemed spoiled due to writing on the ballot paper, if no clear first preference is marked for a candidate, or if the ballot paper was not stamped by the presiding officer or polling clerk.
The quota is then calculated on the basis of the total valid poll. The quota is the figure that, if reached, guarantees the election of a candidate. It is possible to get elected without reaching the quota, but this can only happen when all other candidates are excluded.
The quota is calculated by dividing the total valid poll by 1 more than the number of available seats, and then adding 1.
For example, in a four-seat constituency with a valid poll of 60,000, the quota would be: (60,000 divided by 4+1) + 1 = 12,001.
The quota is a formula calculated on the basis of the lowest possible number of votes that can be filled by the number of candidates to be elected.
Votes are transferred after each count when a candidate is either elected or eliminated. A vote can be counted multiple times with transfers.
Any preference for candidates who have already been elected or have been excluded is ignored. The next available preference on the ballot paper is used.
If a voter picks only one candidate, their vote cannot transfer because they have no second preference. A voter can influence the election of other candidates by continuing to vote down the list of candidates.
When a vote is transferred it counts as a full vote even if it’s a number 8, ie the voter’s eighth preference. That is why it’s called a single transferable vote.
Candidates remain in the count as long as they keep receiving sufficient transfers to remain in contention. This process is repeated until there are no more votes to be transferred.
A number of other countries, including Malta, use the PR-STV system, as does Northern Ireland for local and Assembly elections.
Two referendums were held, in 1959 and 1968, to try to replace PR-STV with the British first-past-the-post system, but both were defeated.
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