Ireland is set to vote in a general election later this month, and has a fairly unique system of deciding who takes their seats in parliament.

In Ireland, all elections – Dail, Seanad, presidential, European and local elections – are decided through proportional representation with a single transferable vote (PR-STV).

Voters indicate their first and subsequent choices for the candidates on the ballot paper by marking the relevant number in the box beside a person’s name. You indicate your first choice by writing ’1′ opposite that candidate and ’2′ opposite your second choice, and so on.

By doing so, you are instructing that your vote be transferred to your second preference if your first choice is either elected with a surplus of votes over the quota or is eliminated.

If your second choice is elected or eliminated, your vote may be transferred to your third choice, and so on.

You can order some or all candidates, or stop at just one. If there’s someone you really don’t want to see elected, it’s best to give preferences to everyone but them. As the count continues and the number of non-transferable votes add up, the number of votes required to be elected decreases.

How are the votes counted?

At the count centre, all the ballot papers are mixed and then sorted according to first preferences. Spoiled papers include votes without an official stamp; those which do not indicate a clear choice (for example, if you have indicated number 1 twice on the paper); and any vote where something is written on the ballot paper by which the voter can be identified. These are removed by people counting the votes.

The quota, the minimum number of valid votes each candidate must get to be elected, is then calculated.

In a three-seat constituency, for example, the quota is a quarter of the valid votes, plus one – only three candidates can get this number of votes. In a four-seater, the quota is a fifth of the valid votes, plus one, and so on.

Surplus votes

If a candidate receives more than the quota on any count, the surplus votes are transferred to the remaining candidates in proportion to the next available preferences indicated by voters.

Citizens Information has given this breakdown as an example:

If candidate A receives 900 votes more than the quota on the first count and, on examining their votes, it is found that 30% of these have next available preferences for candidate B, then candidate B does not get 30% of all candidate A’s votes, candidate B gets 30% of A’s surplus, that is, 270 votes (30% of 900).

Where a candidate is elected at the second count or a later one, only the votes that brought them over the quota are examined in the surplus distribution – i.e. the votes last transferred to the elected candidate.

The manner in which the surplus is distributed depends on whether the number of transferable papers is greater than, less than, or equal to the surplus.

If two or more candidates exceed the quota at the same time, the larger surplus is distributed first. The surplus must be distributed if it can elect a candidate or save the lowest candidate from elimination or qualify a candidate to recoup their election expenses or deposit.

Candidates at most elections can recoup their election expenses provided the number of votes they receive at the count exceeds one quarter of the quota.

The last seat can be filled either by a candidate exceeding the quota or being elected without reaching the quota because it is clear that they are ultimately going to be elected.

Candidates can ask for a recount of a particular count or of the entire count.

Pros and cons

Some people argue the PR-STV system is too candidate-focused and leads to localism – i.e. TDs focusing on issues in their local area, rather than pursuing a national vision.

A 2011 Oireachtas report found that this might deter nationally-minded individuals from entering politics, as well as poor national planning “as legislators clamour to deliver services to their own areas”.

However, the report also notes there are “equally profound problems with the likely alternatives to PR-STV”, stating: “If local accountability is reduced, a clearly articulated ‘national interest’ to which parliamentarians are accountable is needed.”

It has been argued the current system leads to more variety for voters – i.e. TDs being returned from a number of parties. However, in constituencies that elect fewer TDs, it can be very difficult for smaller parties to gain a significant foothold.

As a result of PR-STV, coalition governments are very common in Ireland. The last single party government here was the 1987-89 Fianna Fail administration.

First past the post

PR-STV is relatively unique, Ireland and Malta are the only countries to use it.

The first past the post system in single-seat constituencies is the second most popular voting system in the world. It’s used in the UK, US, India and Canada.

The candidate with the most votes in each constituency becomes an MP. All other votes are disregarded. This type of voting is also known as single member plurality, simple majority voting or plurality voting.

The Oireachtas report mentioned above also looked into various other types of voting, such as alternative or preferential voting, and the closed list system.

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