The proposed boundary changes for Parliamentary constituencies aim to provide greater equality for the electorate, but will entail significant redrawing of boundaries and changes in constituency demographics.

About the research

In September 2016 the Boundary Commissions for England, Northern Ireland and Wales published initial proposals for new Parliamentary constituencies; Scotland’s appeared a month later. These implement new rules, designed to ensure greater equality of electorates across constituencies. The government’s rationale for greater equality of electorates appeals to the ‘one person, one vote’ democratic principle.

The number of constituencies is being reduced from 650 to 600, all of them (with four exceptions) to have electorates within five per cent of the national average of 74,769. The reduction in  constituencies will reduce the size of the House of Commons, suggested to save an estimated £12 million.

Ron Johnston OBE, Professor of Geography at Bristol University, has explored issues connected to the proposed boundary changes. His main research interests are in electoral studies, urban social geography and the history of geography

Key points

  • The boundary changes involve considerable change in the allocation of seats across the UK. In England, for example, the Commission’s proposals leave only 68 of the current 533 constituencies unchanged.
  • Most MPs will face significant disruption to their seats and have to build relationships with new areas, perhaps with very different population make-ups and social, economic and cultural issues.
  • An allowed variation of 10 per cent (rather than five per cent) around the national average constituency electorate would have generated less disruption to the current map. However, the current geography of support for the three main parties (Conservative, Labour and the SNP) means that many seats are unsafe at any rate, and can change hands without large swings.
  • Although the overall reduction of MPs is eight per cent, both England and Northern Ireland receive only six per cent cuts (from 533 to 501 and 18 to 17 respectively). Scotland receives a 10 per cent cut (from 59 to 53). For Wales it is nearly three times that, at a cut of 28 per cent (from 40 to 29).
  • The new configurations are much less confined within single local authorities than currently. For instance, Birmingham currently has 10 constituencies, each comprising four of the city’s 40 wards. Two of the 10 constituencies will remain unchanged, while three others will comprise four Birmingham wards each, and the remaining will combine parts of different wards. Several of these new seats combine places with few common interests and close ties; disparate places have been combined simply to meet the numerical rules.
  • Labour has traditionally benefited substantially from variations in constituency electorates, winning seats on average smaller than the Conservatives’. Equalisation of electorates removes this pro-Labour advantage and widens the gap between the two. Closing that gap will be  difficult because of the marginality of the new seats.
  • To become the largest party, let alone win a majority, in 2020 the Labour party will need to overturn leads of 10 percentage points or more in a substantial number of seats being defended by the Conservatives and SNP.
  • If the electoral register had included the 1.8 million people removed in late 2015, Labour might have benefited slightly, but probably not by enough seats to make a substantial difference.
  • The geography of party support underlying the current and probable new constituencies means a more divided country electorally than previously, and makes the likelihood of change on the government front benches very unlikely without a major change in the pattern of
    voters’ preferences.