A significant number of returning officers could face the added complications of handling elections which cross council boundaries under a review of parliamentary constituencies, the Association of Electoral Administrators has warned.
The Boundary Commission’s guide on how it will reduce the number of MPs in the House of Commons from 650 to 600 said it would be “often necessary” to create seats which do not fit with established council areas.
The commission said this is due to a requirement to fit the number of voters in each constituency within a 10% range of an “electoral quota” of 74,769.
The review would see the number of constituencies in England reduced from 533 to 501.
The commission said it proposes to identify constituencies with reference to external local authority boundaries “as far as practicable” and would use wards as “basic building blocks”.
It added that wards should only be split in “exceptional and compelling” circumstances as this would “break local ties, disrupt political party organisations, and cause difficulties for electoral registration and returning officers”.
Such circumstances cited include where “whole ward options… would significantly cut across local ties” and when splitting a ward would prevent a “significant domino effect of otherwise unnecessary change to a chain of constituencies” to meet the electoral quota.
Chief executive of the Association of Electoral Administrators, John Turner, said the proposals are likely to lead to the number of constituencies crossing council boundaries increasing significantly.
He added: “This will also result in an unprecedented number of returning officers who are dealing with complex cross-boundary issues which make a tough job more difficult.
“Arrangements will need to be made with neighbours to do whatever is necessary to sort out postal voting and making sure ballot papers get back in practical ways to ensure the count is conducted.”
Mr Turner said there was also the added complication of a number of polls planned for May 2020, when the findings of the review would be implemented once new legislation is passed.
These include the London mayoral and Greater London Authority elections, mayoral elections in combined authorities and a likely general election.
Mr Turner added: “There could be up to five different ballot papers and electoral systems, which is unprecedented.
“We will be putting down a marker to government to defer some of the elections to a later time.”
The Boundary Commission’s decision to base its proposals on numbers on the electoral register in 2015, rather than the more recent one compiled for the European Union referendum this year has been criticised by the Electoral Reform Society for failing to account for up to 2 million voters.
Mr Turner said he agreed with the society’s conclusions, adding that latest register was the most accurate and would ensure a more “scientific” approach.
The Boundary Commission has been approached for comment.