We’re used in the UK to the first past the post system (FPTP) for elections to the Westminster parliament; and in N Ireland we’re used to the single transferable vote (STV) for our local elections. There are a surprising number of other voting systems used for official business in the UK. Six systems are used by the public to elect members of parliaments or assemblies, or to elect single officials. One system is only used within the Westminster Parliament.
1 FPTP This is a simple majoritarian system, the winner takes all. It’s suitable when there are only two candidates; there are single-member constituencies. If there are more than 2 candidates, the ‘smaller’ parties tend to do badly. Westminster elections used to be straight fights between Labour and Conservative, or between a Unionist and a Nationalist. No longer.
2 STV This is an attempt at proportional representation. Electors number the candidates in their choice of order; electors may choose as many or as few candidates as they please. There are several ways to determine the quota, the number of votes a candidate must get. It’s a multi-member constituency system; one criticism is that in sparsely populated, remote areas it produces geographically very large constituencies. STV is used in N Ireland for Assembly, European and local councils. It’s used in Scotland for local elections.
3 AMS (Additional Member System) This is used in Scotland for Parliamentary elections; in Wales for elections to the Assembly there, and in London for the Assembly. You have a vote for a person, and another vote for a political party. The constituencies are single member, and the winner is decided by FPTP, or the ‘second ballot’ or AV (Alternative vote).
4 AV (Alternative Vote) In this, candidates (for an office) are ranked 1, 2, 3 etc. A candidate needs a 50% threshold to win. If no one is successful on the first round of voting, the candidate with the fewest first preference votes is eliminated, and these votes are redistributed; the process continues until one elected candidate emerges. AV is used to elect the Lords Speaker—since reforms of the Lords, the Lord Chancellor is no longer Speaker; it’s used for by elections for replacement hereditary peers, and for most of the chairs of committees in the House of Commons. AV is another majoritarian system—it isn’t proportional representation; it was the alternative to FPTP in the referendum a few years ago.
5 SV (Supplementary Vote) This is similar to AV, though there is only a first and second preference choice allowed—a cross in one column for the first preference, and a cross in the second column for the second preference. This is used to elect the mayors in Britain, such as the Mayor of London and elsewhere.
6 CPL (Closed Party List) This is used in multi-member constituencies in Great Britain for European Parliament elections. Electors vote for a party, not for a candidate, with an X. The parties get seats in proportion to the votes cast. The political parties determine the order of their candidates.
7 PAL (Plurality-at-large) This system is used for some local elections in England and Wales—most of these local elections are by FPTP. PAL is a non-proportional system, rather like a block vote.
There are even more voting systems, as described on the website of the Electoral Reform Society, here.
Unsurprisingly, following the 2015 general election, there have been calls for the UK electoral system to be changed. These calls come from parties who have received seats out of proportion to the overall votes cast for them. And there are those who seem to think that the UK voting system has remained unchanged for centuries, so why should it change now. These latter are mistaken; voting systems and constituencies have been changing from the Great Reform Act in the early 1830s. This Act removed ‘rotten’ or ‘pocket’ boroughs, those where a tiny number of voters elected two members to ‘represent’ them, while attempting a degree of representation to industrial conurbations which hitherto had had been unrepresented. Until the 1950 general election, there were still some multi-member constituencies in the UK, with members being elected by ‘block vote’ or ‘limited vote’; and MPs elected to represent universities were elected by STV.
After voting systems, there are questions about the franchise, who gets to vote and who doesn’t; and the size of constituencies, by how much the electorate could vary from the average, whether some constituencies should be ‘protected’, and who decides all this—politicians or independent commissioners.