Parliamentary Boundary Reviews: What Next? Contents

2Alternatives to implementing the 2018 Review

26.Until a new set of boundaries are implemented by an Order in Council approved by both Houses of Parliament the old boundaries remain in-force. The Boundary Commissions will not, under the current legislation, produce another set of proposals until 2023.45 The current boundaries were first used in 2005 in Scotland and 2010 in the rest of the UK.46 However the electoral registration data that was used to carry out those reviews was taken from 2000 in England, 2001 in Scotland and Wales, and 2003 in Northern Ireland.47 Hence by 2022 the majority of seats would be drawn on the basis of 22 year old data.

27.As Professor Johnston explained, while the movement of population between urban and rural areas during most of the post war period that had tended to disadvantage the Conservative Party, has ended;48 there is still significant change in the number of electors between seats over even short periods of time. From 2015 to 2016, for instance, the change in individual constituency electorates ranged from an 11.1% increase in Cardiff Central to a 6.7% decrease in Belfast West.49

28.As set out in paragraphs 12 to 14 above the current boundaries also reflect the old rules, with their substantial differences in constituency size. For example constituencies in Wales had an average of 57,045 electors per constituency at the 2015 election, compared to an average of 72,676 in England.50 Professor Scully argued that the devolution of primary law making powers to the National Assembly for Wales meant this should be ended, in-line with the changes in Scotland following the creation of the Scottish Parliament.51 As Steve Halsall of the Boundary Commission for Wales explained, using a UK wide electoral quota in the 2018 review reduces the number of Welsh seats from 40 to 29.52

29.Within the current legislation, the only alternative to the old boundaries would be the recommendations the Boundary Commissions make in September 2018 drawn using the rules in the 2011 Act and implementing the reduction of MPs to 600. If the legislation is not amended the subsequent review, due in 2023, will be carried out based on the rules in the 2011 Act whether the 2018 Review is implemented or not. However, as the Boundary Commissions made clear in their evidence to us it is within Parliament’s powers to change the rules and ask the Commissions to make new proposals.53

30.One attempt to do this, the Parliamentary Constituencies (Amendment) Bill, received its second reading in the House of Commons on 1 December 2017.54 This is a Private Members’ Bill introduced by Afzal Khan. It would increase the allowed variance from the electoral quota to 7.5%, fix the number of MPs at 650 and require a new boundary review.55 We have not considered the merits of the Bill and make no conclusion on them.56 However, the fact that the Bill, which was supported at second reading by 214 Labour MPs,57 accepts the principle that the number of MPs should be fixed and the same electoral quota used across the UK, fundamental components of the 2011 Act, suggests that there may be scope for cross party consensus on potential legislation.

31.Any new review would also use more up to date electoral registration data than the 2018 Review. This would address the concerns raised by Mr Khan and others that the December 2015 data which the Commissions, by law, have based the 2018 review on does not reflect the rise in registrations as a consequence of the EU referendum in 2016 and the General Election in 2017.58 There were 2.1 million more registered voters in June 2017 compared to December 2015.59

32.The Government cannot be confident that the House of Commons will support the implementation of the Boundary Commissions’ recommendations in the autumn. The existing boundaries are based on data that is more than two decades old. Furthermore, they were drawn using rules that do not reflect the current reality of devolution in the UK. Therefore, using the existing boundaries is not a step that should be taken lightly given the significant influence that boundaries have on our elections. Amending the current legislation to facilitate a boundary review process that would command broader support in Parliament, and have updated boundaries in place by a General Election 2022, is therefore worthy of serious consideration. The Parliamentary Constituencies (Amendment) Bill suggests that, if there were will on both sides of the House to compromise, it would be possible to develop new rules that could attract broader support. It may provide Parliament and Government with a vehicle for debating and implementing legislative change.


45 Parliamentary Constituencies Act 1986, Section 3(2) (as amended by the Electoral Registration and Administration Act 2013)

46 Prior to the 2011 Act reviews could be implemented separately as each nation had a separate allocation of seats and electoral quota.

47 Q88; Boundary Commission for Scotland “Fifth Periodical Report of the Boundary Commission for Scotland”, CM 6427, December 2004, para 7; Boundary Commission for Northern Ireland “Recommended Parliamentary Constituencies”, 3 October 2007.

48 Q81

49 Such large shifts in electorates are likely to be owing to changes in practice by the local electoral authority or an event causing an increase in registration locally, rather than shifts in population. However constituencies are drawn on the basis of numbers of registered electors rather than the local population. Office for National Statistics “Electoral Statistics for the UK: 2016, 16 March 2017

50 Curtice “The Geographical Challenge”

51 Q75 [Professor Scully], the National Assembly for Wales was granted primary law making powers in 2011, and the Wales Act 2017 introduced a ‘reserved powers’ model similar to the Scottish Parliament.

52 Q11

53 Q20

54 Mr Khan’s Bill is a private members bill introduced through the ballot procedure. Parliamentary Constituencies (Amendment) Bill [Bill 009 (2017–19)].

55 N. Johnston, “The Parliamentary Constituencies (Amendment) Bill 2017–19”. The size of the Commons peaked at 659 MPs following the implementation of the 4th Periodic Review in 1997 before being reduced to 650 by the 5th Periodic Review, Gay & White “Parliamentary Voting System and Constituencies Bill 2010”

56 In their supplementary written evidence, the English, Welsh and Northern Irish Commissions raised technical concerns about some details of the Bill, including the implied truncation of the time allowed for a review. Letter from Sam Hartley, 24 January 2018.

57 HC Deb, 1 December 2017, Col 637-638

58 HC Deb, 1 December 2017, Col 590. There was also a surge in registrations reported in Scotland in 2014 prior to the referendum on independence, “Scottish Independence: 97% register to vote in referendum The Guardian 11 September 2014. As far as these new voters over the age of 18 who remained on electoral register in December 2015 they will have been taken into account by the Scottish Boundary Commission.

59 N. Johnston “The Parliamentary Constituencies (Amendment) Bill 2017–19”




16 February 2018