Electoral Systems GapFill

For the purpose of general elections, the UK is currently divided into  650700550500 parliamentary constituencies (though the number of constituencies and their boundaries can change over time depending on changes in the population). Each parliamentary constituency elects one Member of Parliament to the House of Commons, meaning a single party must win  351326251276 MPs in a general election in order to form a  hung parliamentmajority governmentminority governmentsofa government. If no single party wins this number of seats, then the election result is known as a  coalition governmentmajority governmentsofa governmenthung parliament and two or more parties may form a  majority governmenthung parliamentsofa governmentcoalition government in order to secure a majority in the House of Commons. This was the arrangement between the Conservatives and Liberal Democrats between 2010 and 2015. Alternatively, a larger party may seek a  minority governmentconfidence and supply agreementhung parliamentsofa government in which smaller parties promise to support the largest party in key parliamentary votes. This was the arrangement between the Conservatives and Democratic Unionist Party between 2017 and 2019. In this scenario, the largest party governs as a  majority governmentsofa governmentminority governmenthung parliament.

The electoral system used in UK parliamentary constituencies is called   the alternative vote systemproportional representationthe additional member systemfirst past the post. In this system, the candidate with the most votes wins, even if they have only a single vote more than their nearest competitor. This system is considered simple and easy to understand, though it is criticised for creating disproportional results, meaning the number of votes and number of seats a party receives are not equal.

Across the UK, many different and more proportional electoral systems are used. For elections to the Scottish Parliament and Welsh Assembly,  the additional member systemthe alternative vote systemthe first-past-the-post systemproportional representation is used. In this system, voters have two ballot papers. The first is the same as in general elections, in which a candidate is chosen for each constituency. On the second ballot paper, voters choose which party they prefer, independently of candidates. This ‘party list’ is then used to allocate more representatives to parties that have received fewer seats than votes. For elections to the Northern Ireland Assembly,  the single transferable vote systemthe additional member systemthe alternative vote systemproportional representation is used. In this system, voters have only one ballot paper but each constituency has multiple representatives. This allows for the seats to be distributed more proportionally according to votes within each constituency. Finally, for the London mayoral elections  the alternative vote systemthe additional member systemproportional representationthe supplementary vote system is used. In this system voters have one ballot paper but a first- and second-preference vote. If no candidate receives a majority of first-preference votes, then all but the top two candidates are eliminated, and second-preference votes are counted to determine which candidate has the most overall support. This system ensures a winning candidate receives support from over 50% of voters.

All of these more proportional systems have been introduced in the UK since 1997 to provide the process of devolution and new forms of government with increased legitimacy and to secure the support of smaller, nationalist parties in each nation. In the special case of Northern Ireland, the electoral system helps to support the peace process by ensuring that each constituency has representation from both the unionist and nationalist communities. As a result of these new electoral systems, the devolved institutions have seen the formation of a large number of  hung parliamentssofa governmentscoalition governmentsmajority governments, with the smaller nationalist parties tending to play a much larger role. The only party to have achieved a  hung parliamentmajority governmentsofa governmentminority government in any election under these systems is the  Scottish National PartyDemocratic Unionist PartyLabour PartyGreen Party in the 2011 Scottish Parliament elections.