Initial proposals for new Parliamentary constituency boundaries in the South East region

2 Background to the 2023 Review

  1. We are currently conducting a review of Parliamentary constituency boundaries on the basis of rules most recently updated by Parliament in 2020.6 These rules require us to make more equal the number of electors in each constituency. This report covers only the work of the Boundary Commission for England (there are separate commissions for Northern Ireland, Scotland and Wales) and, in particular, introduces our initial proposals for the South East.
  2. The legislation states that there will be 650 Parliamentary constituencies covering the UK – the same as the current number. England has been allocated 543 constituencies for the 2023 Review, ten more than there are currently. There are also other rules that the Commission has regard to when conducting the review – a full set of the rules can be found in our Guide to the 2023 Review7 published in May 2021, but they are also summarised later in this chapter. Most significantly, the rules require every constituency we recommend (with the exception of two covering the Isle of Wight) to contain no fewer than 69,724 electors and no more than 77,062.
  3. This is a significant change to the old rules under which Parliamentary boundary reviews took place, in which achieving as close to the average number of electors in each constituency was an aim, but there was no statutory fixed minimum and maximum number of electors. This, together with the passage of time since constituencies were last updated (based on data from 2000), means that in England, existing constituencies currently range from 54,551 to 111,716 electors. Achieving a more even distribution of electors in every constituency across England, together with the increase in the total number of constituencies, means that a significant amount of change to the existing map of constituencies is inevitable.
  4. Our Guide to the 2023 Review contains further detailed background information, and explains all of the policies and procedures that we are following in conducting the review. We encourage anyone wishing to respond to the review to read this document, which will give them a greater understanding of the rules and constraints placed on the Commission, especially if they are intending to comment on our initial proposals and/or make their own counter-proposals.
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The rules in the legislation

  1. As well as the primary rule that constituencies must have no fewer than 69,724 electors and no more than 77,062, the legislation also states that, when deciding on boundaries, the Commission may take into account:
    • special geographical considerations, including in particular the size, shape and accessibility of a constituency;
    • local government boundaries which existed, or were prospective, on 1 December 2020;
    • boundaries of existing constituencies;
    • any local ties that would be broken by changes in constituencies; and
    • the inconveniences attendant on such changes.
  1. In relation to local government boundaries in particular, it should be noted that for a given area, where we choose to take account of local government boundaries, if there are prospective boundaries (as at 1 December 2020), it is those, rather than existing boundaries, of which account may be taken. This is a significant change to the former legislation, which referred only to the local government boundaries as they actually existed on the relevant date.
  2. Our initial proposals for the South East (and the accompanying maps) are therefore based on local government boundaries that existed, or – where relevant – were prospective, on 1 December 2020. Our Guide to the 2023 Review outlines further our policy on how, and to what extent, we take into account local government boundaries. We have used the existing and prospective wards as at 1 December 2020 of unitary authorities, and borough and district councils (in areas where there is also a county council) as the basic building blocks for our proposals.
  3. In a number of existing constituencies, changes to local government wards since those constituencies were last updated (in 2010) have resulted in the new ward effectively being split, between the constituency the old ward was wholly a part of, and at least one other existing constituency. As part of our proposals, we will by default seek to realign the boundaries of constituencies with up-to-date ward boundaries, thus reuniting wards that are currently divided between existing constituencies. In places where there has been only minor change to a ward, this may see an existing constituency boundary change only very slightly to realign with the new ward. However, where wards in an area have been changed more significantly, this may result in the area covered by the new ward becoming part of a different constituency than the one in which the area was previously.
  4. Although the 2023 Review of Parliamentary constituencies will inevitably result in significant change, we have also taken into account the boundaries of existing constituencies so far as we can. We have tried to retain existing constituencies as part of our initial proposals wherever possible, as long as the other factors can also be satisfied. This, however, has proved difficult. Our initial proposals retain just over 15%8 of the existing constituencies in the South East region – the remainder are new constituencies (although in a number of cases the changes to the existing constituencies are fairly minor).
  5. Our proposals are based on the nine English regions as defined in the legislation: a description of the extent of each region also appears in the Guide to the 2023 Review. This report relates to the South East region. There are eight other separate reports containing our initial proposals for the other regions. You can find more details in our Guide to the 2023 Review and on our website. While our use of the regions does not prevent anyone from making proposals to us that cross regional boundaries (for example, between the South East and South West regions), very compelling reasons would need to be given to persuade the Commission to depart from the region-based approach. The Commission has previously consulted on the use of the English regions as discrete areas, and this was strongly supported.
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6 The Parliamentary Constituencies Act 2020, available at www.legislation.gov.uk/ukpga/2020/25/contents
7 Available at www.bcereviews.org.uk and at all places of deposit.
8 This figure excludes constituencies that have been changed only to realign with changed local government boundaries.

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