Voting Systems

How it worksUnder FPTP, voting takes place in constituencies that elect 1 MP each. Voters put a cross in the box of their preferred candidate and the candidate with the most votes is elected.

Where it is used
UK House of Commons, US Congress, Indian lower house 

Positives
It's simple to understand. It doesn't take long to count votes. Tends to produce a two-party system which results in a stong one-party government. Parties have to appeal to the centre ground to win votes.

Negatives
Candidates can get elected on tiny amounts of support. It encourages tactical voting. Majority of votees are wasted. Severely restricts voter choice. FPTP rewards parties with concentrated bases of support rather than actual support. Encourages gerrymandering. Encourages safe seats. Third parties with significant support are greatly disadvantaged. 

How it works
Two columns on a ballot paper - one for first choice, one for second choice. All first choices counted and if candidate gets majority, they are elected. If no winner in first count, second choice votes of losing candidates are reallocated.

Where it is used
All directly elected English mayors, Police and Crime Commissioners in England and Wales

Positives
Encourages conciliatory campaigning as second preference votes are important. Relatively simple to understand.

Negatives
Does not ensure winner has 50% of vote. Promotes only voting for 3 main parties. Voters must guess which candidates will get into final round - if they guess wrong their vote is wasted. Does not eliminate tactical voting. 

How it works
Voters rank candidates in order of preference. If a candidate gets more than 50% they win. If not, the losing candidates have their second preference votes reallocated until someone has more than 50%.

Where it is used
Labour and Liberal Democrat leadership elections, Australian House of Representatives, Irish Presidential Elections

Positives
All MPs have support of majority of voters. Retains same constituencies as FPTP. Penalises extremist parties. Encourages candidates to chase 2nd and 3rd preference votes. Reduces need for tactical voting. Reduces number of safe seats. 

Negatives
Can be more disproportionate than FPTP. Compromise candidate can be eliminated in 1st round. Lower preferences can produce winners with little of their own support. Prone to donkey voting.

How it works
Voters rank candidates in order of preference. Candidates need a quota of the vote determined by size of constituency and number of positions to be filled.

Where it isused
Ireland, Northern Ireland, Scottish local elections, Australian senate, Indian upper house

Positives
Gives voters more choice. Fewer votes are wasted. Parties have incentive to present balanced team of candidates. Offers choice of MPs to go to with problems. Parliament more representative. All MPs elected on same basis. No safe seats. No need for tactical voting. 

Negatives
Could lead to very large constituencies. Counting votes takes longer. Prone to donkey voting. Voters only tend to come into contact with candidates at election time. Ballot papers can get big and confusing.

How it works
Parties present list of candidates and seats are awarded according to share of vote. Open list - voters choose individual candidates who are elected via popular vote. Closed list - voters vote for paty and therfore list as a whole. Candidates are elected in order they appear on list until all seats are filled. 

Where it is used
British elections to European Parliament, over 80 countries including Israel, Brazil, Russia, Austria

Positives
High degree of party proportionality. Every vote has equal value. Very simple. More opportunities for women and minorities. Open list offers more choice to voters.

Negatives
Closed party lists weaken link between MP and constituency. Closed list offers little choice for voters. Under-represented groups low on lists. Closed lists can stifle minority opinion. Difficult to stand as an independent. Can produce unstable, multi-party governments. 

How it works
Voters choose one candidate to represent them in their constituency and then choose one party to represent them in a larger regional constituency. This combines FPTP and List systems. Each constituency returns 1 MP and party list candidates are allocated on top of these constituency seats so the number of seats a party has represents their share of the vote.

Where it is used
Scotland, Wales, Greater London, Germany, New Zealand, Mexico, Bolivia, Lesotho

Positives
Broadly proportional. Directly accountable MP. Each voter has at least 1 effective vote. Allows voters to express support for a candidate without going against their party.

Negatives
Many MPs accountable to leadership rather than voters. Two different classes of MPs creates animosity. Can lead to 'overhang seats' where a party has more constituency seats than they are entitled to. Can be complicated.

How it works
Voters choose preferred candidate with a cross and if one candidate gets more than 50% they are elected. Otherwise another ballot normally featuring the top two candidates is heald. The winner of the second ballot is elected.

Where it is used
France, heads of state of a number of European countries

Positives
Slightly more representative than FPTP. Less need to vote tactically in first round. Encourages parties to be friendly with each other. Easy to understand. Easy to count.

Negatives
Wasted votes. Highly disproportional. Voting process drawn out. Can lead to surprising outcomes if compromise candidate does not reach 2nd round. Can foster disillusionment by excluding smaller parties. Can lead to candidates standing down in 2nd ballot to exclude a third.