The government is under fire for quietly removing a requirement on town halls to canvas all homes every year to sign up voters, including household visits if there is no response to letters.
The new “light touch approach” would see people in some homes contacted electronically only, or through a manager in properties of multiple occupation.
MPs voted through the change on Thursday – even though the elections watchdog has said trials of the shake-up showed it was not ready to be put in practice.
The Cabinet Office’s own evaluation there was a risk of people being “ostracised” if they were “less IT literate” and of some potential voters “being missed”, Labour pointed out.
“We are very concerned that there is a real risk that the proposed reform will have a detrimental impact on the accuracy of the register, particularly for under-represented groups,” said Cat Smith, the party’s voter engagement spokeswoman
“This is a very significant and complicated piece of legislation that requires proper scrutiny and shouldn’t be rushed through days before we embark on a general election campaign.”
The controversy comes after Boris Johnson was widely criticised for plans to force voters to show identification at polling stations – despite warnings that legitimate voters would be turned away.
The Cabinet Office has been asked to comment on the criticism that the overhaul of canvassing is being rushed through.
The pilots were carried out in 2016 and 2017 because the switch to individual – rather than household – registration made traditional canvassing inefficient and expensive, the government argued.
Some 88 per cent of homes were responding “simply to report that nothing has changed in the composition of their household”.
Streamlining it would to allow councils to “re-focus their available resources on targeting citizens who were not currently registered, particularly those from under-registered groups”, it said.
Ministers have now adopted a “hybrid” model, under which existing data is used to identify households where no-one has moved in or out, which would only be “lightly” canvassed.
Those given a “red light” would still be contacted up to three times, but this could be “by email, SMS text, telephone, in person or electronically through a council account”.
Ms Smith said Labour supported a review of canvassing, but provided it did not jeopardise ensuring “the electoral register is as accurate as possible”.
Around 9 million people are already missing from the rolls, with only 71 per cent of 18 to 34-year-olds registered compared with 93 per cent of over-55s.
No less than 91 per cent of home owners are registered, but only 58 per cent of private renters.
But a Cabinet Office spokesperson said: “We have been working with the electoral community for four years to modernise the annual canvass - this included a public consultation where the feedback was overwhelmingly in favour of our proposals.
“The changes will allow electoral service teams to streamline their resources far more effectively, freeing up their time to focus on groups less likely to be on the register and keep citizens at the heart of the process.”
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