My Lords, I do not see why that should be the case.
It is also not straightforward to determine the number of people missing from the register. Although it would be possible to match population estimates against registration numbers to generate a notional rate, population data are estimated and would include some people who are not eligible to register to vote due, for example, to nationality. The Electoral Commission itself, in its recent report on underregistration, calls the process of estimating registration rates "an imprecise science" and says:
"All current approaches to estimating the completeness and accuracy of the electoral registers at a national level are imperfect".
The House has already heard about the limitations of the population data that would inevitably be the basis of any estimation. We will return to this in the next group of amendments.
Introducing estimated figures-acknowledged as imprecise and imperfect-into the calculation of constituency size risks introducing inaccuracies or inconsistencies across the UK, as my noble friend Lord Rennard pointed out. In the interests of a fair and equal system, where each person's vote across the UK has the same weight, constituencies should be calculated on the basis of registered electors, as the Bill proposes. To do otherwise would be to perpetuate a situation in which some votes are more equal than others.