How do the UK's electoral systems work, and which produces the fairest outcomes?
Elections and electoral systems: the functions of elections, first-past-the-post and the proportional and mixed systems used in the UK, and debates about which system is fairest.
A WJEC AS Unit 2 study of elections and electoral systems: the functions of elections, how first-past-the-post works and its effects, the additional member system used for the Senedd, other systems such as STV and SV, and debates about proportionality and reform.
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What this dot point is asking
This WJEC AS topic asks you to explain the functions of elections and how the UK's electoral systems work, and to evaluate which produces the fairest outcomes. You need confident detail on first-past-the-post and on the proportional and mixed systems used in the UK, especially the additional member system used for the Senedd, plus the debate about reform.
The answer
The functions of elections
First-past-the-post
Typical effects of FPTP include a "winner's bonus" for the largest party, the under-representation of third parties, many "wasted" votes, and the importance of marginal seats.
Proportional and mixed systems in the UK
The UK uses more proportional systems for devolved and other elections.
- Additional member system (AMS). Used for the Senedd and the Scottish Parliament. Voters have two votes: one for a constituency representative (elected by FPTP) and one for a regional party list. The list seats are allocated to make the overall result more proportional, balancing a constituency link with fairer representation.
- Single transferable vote (STV). Used in Northern Ireland and for Scottish local elections. Voters rank candidates in multi-member constituencies, producing highly proportional outcomes.
- Supplementary vote (SV). Historically used for some directly elected mayors, where voters mark a first and second choice.
The debate about reform
The central question is whether Westminster should replace FPTP with a proportional system. Supporters of reform stress fairness and representation: PR systems waste fewer votes and represent smaller parties more accurately, as AMS does for the Senedd. Defenders of FPTP stress strong, accountable government: it usually produces a clear single-party majority and a strong constituency link, while PR can give small parties disproportionate influence and produce unstable coalitions.
Examples in context
Two systems, two effects. Wales itself illustrates the trade-off at the heart of this topic. Senedd elections use the additional member system, so a voter casts a constituency vote and a regional list vote, and the list seats top up the result to make it more proportional, helping smaller parties win representation they would struggle to gain under first-past-the-post. Westminster elections in the same Welsh seats use first-past-the-post, which tends to concentrate seats in the largest parties. Comparing the two shows precisely why the reform debate weighs proportional fairness against strong single-party government.
Try this
Q1. What does first-past-the-post require a winning candidate to obtain? [2 marks]
- Cue. The most votes in the constituency (a plurality), not necessarily a majority of votes cast.
Q2. Which electoral system is used to elect the Senedd? [1 mark]
- Cue. The additional member system (AMS), a mixed system combining constituency and regional list seats.
Q3. To what extent should the UK replace first-past-the-post with a proportional system? [25 marks]
- What the marker wants. A judgement weighing proportional fairness and representation against strong, accountable single-party government, using UK and Welsh examples.
Exam-style practice questions
Practice questions written in the style of WJEC exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.
WJEC AS Unit 210 marksExplain how the first-past-the-post electoral system works.Show worked answer →
A short-answer question testing AO1 knowledge of electoral systems.
Under first-past-the-post the UK is divided into single-member constituencies. Each voter casts one vote for one candidate, and the candidate with the most votes (a plurality, not necessarily a majority) wins the seat. The party that wins most seats nationally usually forms the government.
The best answers explain the single-member constituency, the plurality rule, and the typical effect of producing a single-party majority government and disadvantaging smaller, evenly spread parties.
WJEC AS Unit 220 marksTo what extent should the UK replace first-past-the-post with a proportional system?Show worked answer →
An extended evaluation requiring a balanced judgement.
Case for reform: first-past-the-post produces disproportional results, wastes many votes, disadvantages smaller parties, and can give a majority of seats on a minority of votes; proportional systems such as the additional member system used for the Senedd give fairer representation.
Case against reform: first-past-the-post is simple, produces strong single-party governments and a clear constituency link, and proportional systems can give disproportionate power to small parties and produce unstable coalitions.
The top band weighs fairness and representation against strong, accountable government and reaches a supported judgement.
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