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The Parliamentary Constituencies Bill 2019-21 was introduced on 19 May 2020. It had its Second Reading in the House of Commons on 2 June 2020. The Bill received royal Assent on 14 December 2020. 

The Bill

The Parliamentary Constituencies Bill 2019-21 will amends the Parliamentary Constituencies Act 1986. The 1986 Act gives the Boundary Commissions their statutory basis, governs the constituency boundary review process and sets the Rules of Redistribution that the Commissions must follow.

If the Bill, as introduced, made the following key changes:

  • The number of MPs will be fixed at 650;
  • The 2018 Review, which would have reduced the number of MPs to 600 will no longer be implemented. Ministers will no longer be required to lay legislation (a draft Order in Council) to implement the 2018 Review.
  • The next review, due to start in 2021, will have to be completed by the Boundary Commissions by 1 July 2023. It will be based on the number of registered electorates as of 1 December 2020;
  • The next review after the 2023 Review will have to be completed by 1 October 2031; with subsequent reviews required to report by the 1 October every eight years thereafter;
  • Recommendations of the Boundary Commissions will be no longer require Parliamentary approval and government ministers will have no power to alter recommendations;
  • The public consultation phase will be amended to allow for public hearings in the secondary stage of consultation rather than in the initial stage. The time allowed for public consultations from 2031 will remain the same overall (24 weeks) but will be split into three eight-week periods. The consultation stages of the 2023 Review will be have a shorter duration as a result of the shorter time available for the 2023 Review.
  • The Boundary Commissions will be given more flexibility to use local government and ward boundaries that have yet to come into force.

The provisions of the Bill extend and apply to the whole of the United Kingdom. The matters to which the provisions of the Bill relate are not within the legislative competence of the Scottish Parliament, the Senedd Cymru/Welsh Parliament or the Northern Ireland Assembly, and no legislative consent motion is being sought in relation to any provision of the Bill.

The Government published Explanatory Notes for the Bill. The Bill page on the Parliamentary website also provides links to an Impact Assessment and a Delegated Powers Memorandum from the Cabinet Office.

Second Reading

The Labour Party tabled a reasoned amendment to the decline to give a Second Reading of the Bill. The reasoned amendment was rejected on division and the Bill then passed its Second Reading without a division.

The key objections to the Bill, as introduced, were

  • the removal of Parliament’s role in having a final say by voting implementing the Commissions’ recommendations;
  • the possible impact of the Coronavirus pandemic on the electoral data to be used for the 2023 Review (electoral registers as they are at 1 December 2020);
  • the interaction between the 5% rule and local ties;
  • the possible impact on the Union of the reduction in seats in Scotland and Wales.

Committee stage

The Committee stage of the Bill made two important changes.

In response to concerns about the completeness of electoral registers during the coronavirus pandemic, the Government agreed to bring forward an amendment at the Committee stage. The amendment altered the data to be used for the 2023 Review as the electoral register of 2 March 2020, before the full impacts of coronavirus took hold.

The Government agreed a backbench amendment to add Ynys Môn to the list of protected island constituencies that are not subject to the strict electoral quota requirements in the Rules of Redistribution. This will be Wales’ first protected constituency.

Remaining Commons stages

The Report stage and Third Reading were taken on 14 July 2020. Opposition members brought forward proposed new clauses in an attempt to widen the 5% tolerance to 7.5% and to guarantee a minimum number of seats for Scotland, Wales and Northern Ireland. An amendment was also tabled to retain Parliamentary approval on the outcome of a review. These issues had been considered at Committee stage and rejected. They were also rejected on Report. A new clause to alter the definition of electorates used in the review process (to allow for estimates of unregistered voters to be included) was note moved.

The Bill then passed its Third Reading without division and was sent to the House of Lords.#

Lords stages

The Bill had its Second Reading on 27 July 2020.

The House of the Lords amended the Bill on its Report Stage. Only one change had Government support: to require the Government to submit a draft Order in Council, implementing the recommendations of the Commission, no later than four months after the reports of the Commissions have all been laid before Parliament unless there are exceptional circumstances. The amended Bill passed its Third Reading on 15 October 2020 and was sent back to the Commons.

Other changes made to the Bill, but which were opposed by the Government, were to hold reviews every ten years instead of eight; to widen the 5% tolerance to 7.5%; a new clause to alter the way Commissioners are appointed to safeguard their independence, and a new clause to require the Secretary of State to lay before Parliament “proposals for improving the completeness of electoral registers for the purposes of boundary reviews”.

Ping pong

On 10 November 2020 the Commons considered Lords amendments. The Commons rejected all the amendments that the Government had opposed in the Lords. The Lords accepted the Commons reasons for rejecting the amendments on 26 November 2020.

The Bill received Royal Assent on 14 December 2020.

Background to the Bill

In March 2020 the Government announced that it would not implement the reduction in the number of seats in the House of Commons to 600. This had been due to happen when the recommendations of the most recent boundary review, the 2018 Review, were implemented. The Review was conducted by the four independent Boundary Commissions, one for each part of the UK.

Under the then existing law, the Boundary Commissions would have been required to start their next review in early 2021, based on the number of registered electors on 1 December 2020. They would also have been required by to base their calculations on 600 seats for the House of Commons. Reviews are currently required every five years.

The Commissions must follow the Rules of Redistribution contained in the Parliamentary Constituencies Act 1986, as amended.

Instead the Government wants to maintain the number of seats at 650. One reason given for the change is that following the UK’s exit from the European Union MPs will have greater workloads. Reducing the size of the House to 600 seats was meant to reduce the cost of politics. The Government estimates the cost of retaining the 50 MPs that would otherwise have been abolished is approximately £116m over ten years, adjusted for inflation.

The Government also said it would require reviews less frequently and abolish the requirement that Parliament should vote to approve the recommendations. The Government is also proposing changes to the consultation requirements.

The Government is not proposing altering the primacy of the rule on the size of electorates of recommended seats. They will still need to be within 5% of the electoral quota.

Parliamentary constituency boundaries are reviewed periodically primarily to keep take account of population movement.

The current boundaries of Parliamentary constituencies resulted from the Fifth Periodical Review. The Fifth Review in Scotland was completed in 2004 and the boundaries first used in May 2005. This was the year the number of seats in Scotland was reduced from 72 to 59 as a result of the re-creation of the Scottish Parliament. In the rest of the UK, the Fifth Review was implemented in time for the May 2010 General Election. The current constituencies are based on registered electors from February 2000 (England), June 2001 (Scotland), December 2002 (Wales) and May 2003 (Northern Ireland).

The last major changes to the Rules of Redistribution were in 2011. The Parliamentary Voting System and Constituencies Act 2011 inserted into the 1986 Act new rules that the Commissions had to follow . The passage of the that legislation is detailed on the Parliamentary web pages for the Act.

It was the 2011 changes, introduced by the Coalition Government of 2010-15, that were meant to reduce the House of Commons from 650 seats to 600. Constituencies had to be within 5% of the electoral quota with the exception of four island constituencies (Orkney and Shetland, Na h-Eileanan an Iar and two seats on the Isle of Wight).

The electoral quota was calculated by dividing the registered electorate of the UK by the number of seats. As the four island seats were protected, this was calculated as the electorate of the UK minus the electorates of the four excepted islands seats which was then divided by 596. Reviews were meant to be conducted every five years.

The first review under the new rules was meant to be completed in 2013. The review was abandoned in January 2013 before final recommendations were produced, and a new deadline for final recommendations was set for 1 October 2018. The reports of the Boundary Commissions were handed to the Government in September 2018.

Once the Commissions hand over their reports their role in the process ends. The UK Government must then lay the reports. This must be done “as soon as may be”. The Government is then responsible for laying a draft Order in Council to give effect to the new boundaries before Parliament “as soon as may be”. Both Houses of Parliament must approve the draft Order.  

A draft Order for the 2018 recommendations has not been produced.

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