Rev. 13 Dec 25
One issue is single-seat v. multi-seat constituencies.
There is much pressure for the introduction of multi-seat constituencies[1], partlularly from members of smaller parties, who justifiably regard themselves as being under-represented in single-seat systems.[2]
All options likely to be considered by the Commission, other than FPTP and PV, entail having multi-seat constituencies. We need to decide whether the advantages outweigh the disadvantages.
Single-seat
– – is what we have now (and hence the default option)
– – in particular, involves no structural or administrative change
– – is simple, easily understood, and requires no complex calculations
– – keeps MP link –
but has the disadvantages that it
– – tends to produces samey MPs, on every characteritic (gender, age, race, religion, …)
– – is, in particular, clearly non-proportional
– – is vulnerable to gerrymandering.
Multi-seat
– – can yield more appropriate representation
but has the disadvantages that it
– – is novel and complex
– – usually entails complex, and sometimes incomprehensible, calculations
– – too easily leads to incoherent and/or unmanageably wide constituencies.
An intermediate, and socially desirable, option could be to go for multi-seat where towns or counties are now artificially divided, but stick to single-seat where there is no obvious non-electoral reason for combining constituencies.[3]
[1] Up to the whole-nation constituency of pure D’Hondt.
[2] The pressure should be greater for the next election when instead of its usual 2½ larger parties the UK seems likely to have 6 smaller parties. But there is unfortunately no chance of introducing any form of multi-seat constituencies before then.
[3] Advocates of STV in particular are often inclined to be too doctrinaire on constituency sizes.