Antifrank looks at The boundaries of reason: the possible shape of the 2020 election

I previously looked back at the impact of demographic changes on party politics from 1992 to 2015.  That’s all well and good, but what changes can we expect for 2020?  To determine that we first need to consider what the new boundaries are likely to look like.

It might be thought that the future musings of the Boundary Commissions are imponderable, but we have quite a lot of clues to go on.  We should use them.

The terms of any boundary review are closely delimited in legislation.  The following will occur unless the law is changed or the proposed boundary changes are defeated in Parliament:

1) The election will be fought on 600 seats.

2) There will be two Isle of Wight constituencies, a constituency for Orkney & Shetlands and a constituency for Na h-Eileanan an Iar.

3) The 600 seats will be allocated between England, Wales, Scotland and Northern Ireland according to a strict formula based on the number of registered voters as at the review date in each.

4) Except for the exceptions already noted, the seats will have a population of 95% to 105% of the average constituency size (there are size requirements that are relevant only in Scotland and Northern Ireland has special rules).

These are pretty prescriptive rules. There are already rumblings among Conservative MPs that the seat count should be kept at 650.  As we shall see, this may be in the interests of individual Conservative MPs but it is unlikely to be in the interests of the Conservative party as a whole.

The next thing to realise is that the Boundary Commissions have already started looking at this once (until their work was brought to a juddering halt by the Lib Dems ganging up on their coalition partners: as we shall see, this was absolutely correct from a narrow party interest).  So we already can see the general direction of travel.

For the moment I’m going to work on the basis of a 650 seat Parliament to explore what difference the boundary review might make.  While this is not what the law currently requires, it makes it easier to see what difference the impact of movements in registered voters might have.

Allocation of seats around the component parts of the UK

So, what should we expect?  The first thing to do is to determine the number of registered voters in each part of the UK.  This will be set at the end of this year, so we don’t have the precise figures, but the numbers from the general election should provide a fairly decent guide.  We have the electoral commission’s preliminary results:

This gives a national total of registered voters of 46,425,476.

I’ve separated these out into the component parts of the UK:

From these we can derive the following totals of registered voters:

Northern Ireland:1,236,683, Wales: 2,282,297, Scotland: 4,094,784, England: 38,811,712

When the seat allocation is eventually determined, it is done by a broadly proportionate approach.  Since we don’t have the relevant registered voter numbers yet, it is pointless doing anything more than a pro rata approach.  If the seat allocation stays at 650, we can expect Northern Ireland to get roughly 17 seats, Wales to get roughly 32 seats, Scotland to get roughly 57 seats and England to get roughly 543 seats (with one seat up for grabs).  If the seat reduction to 600 seats takes effect, we can expect Northern Ireland to get roughly 16 seats, Wales to get roughly 30 seats, Scotland to get 52 or 53 seats and England to get 501 or 502 seats.  This is almost exactly what the allocation would have been if the boundary review had gone ahead last time.  So much for all the fuss about the voter registration changes.

Either way, English MPs will become still more dominant in Parliament.  This can only be good news for the Conservatives, whose who dominate much of England and rely on it for almost all of their seats.

Allocation of seats within England

Just as important as how the seats are distributed in the UK is how the seats will be distributed in England.  The Boundary Commission for England is not legally obliged to follow the same approach when allocating seats between English regions, but in practice it intended to do so in the last Parliament and I expect it to do so again this time.

The English regions had registered voter totals at the general election as follows:

Eastern: 4,364,656, East Midlands: 3,350,769, London: 5,401,616, North East: 1,941,841, North West: 5,240,724, South East: 6,419,548, South West:4,076,494, West Midlands: 4,140,587, Yorkshire & the Humber: 3,875,477

This would result in the following seat allocations, based on England having 543 seats in a 650 seat Parliament (I have assumed a 650 seat Parliament for ease of comparability):

*Plus two Isle of Wight constituencies

Again, this seems to benefit the Tories.  More seats are being added in their strongest areas while the seat count in the North West and the North East, two of their weaker areas, continues to decline.

Putting numbers on these changes

So, what would these movements mean in real seat numbers?  Unfortunately, we cannot simply apply a formula because much depends on how the boundaries are actually set.  Thinking about the detail of boundary commission reviews will need to be the subject for another post, but some general principles can be laid down now.

1) Boundary reviews are bad for incumbents.  The more extensive the boundary alterations, the less of an advantage incumbency gives.

2) Within an area, a seat reduction will increase the advantage of the party with the most support.  To give an extreme example, if Wales were reduced to one constituency, Labour would expect to take 100% of seats in the area.  Considered on a wider scale, it would obviously be to Labour’s detriment to have only one seat within Wales, but within Wales itself it would accentuate its political dominance.

3) With a seat reduction in an area, regional strength of trailing parties will outweigh general strength in the area.  For example, if Wales were reduced to four constituencies, Labour might reasonably hope to take all four constituencies.  But it would probably be most worried about losing a seat to Plaid Cymru because of its regional strength in north west Wales.  The fact that the Conservatives poll twice Plaid Cymru’s vote share across Wales as a whole would not affect this calculation.

4) An increase of seats in an area will naturally tend to produce more seats for the dominant party in the area, but the increased granularity may help another party gain an odd seat where a pocket of support has previously been swamped by the dominant party’s support in previously-attached areas (this is the inverse of the last two points).  For example, Peterborough is a Conservative-held marginal seat comprising a city with outlying areas attached.  Making the reasonable assumption that the city is more Labour-leaning than the outlying areas, I infer that if the seat count in the area were increased and the boundaries are confined more tightly around the town, Labour might hope to pick up a new seat in an area of Conservative dominance.  Incidentally, this will tend to work better for Labour than for the Conservatives, given the way in which Labour support tends to cluster in towns.

With these principles in mind, and without going through the detail of my thought process (which is more art than science in any case), my guess is that if the votes cast in May were cast on the boundaries of a new 650 seat Parliament that I have outlined above, the seat count would be something like:

Conservative: 335, Labour: 229, SNP: 55, Lib Dem: 8, Plaid Cymru: 3, UKIP: 1, Green: 1, Speaker: 1, Northern Irish parties: 17

So I imagine a hypothetical increase in the Conservative majority by ten or so, but it wouldn’t fundamentally alter the dynamics of the next election.  I feel that I have made midpoint assumptions in coming to these numbers.

The impact of switching to a 600 seat Parliament

But as the law stands, the boundary review will be conducted on the basis that we will get a 600 seat Parliament, and that will intensify some of the effects that I have just noted.  The new 600 seat Parliament would be comprised roughly as follows:

Scotland: 52, Wales: 30, Northern Ireland: 16, England: 502, – Eastern 56 – East Midlands 43 – London 70 – North East 25 – North West 68 – South East 83 (including two Isle of Wight constituencies) – South West 53 – West Midlands 54 – Yorkshire & The Humber 50

The seat reorganisation would be relatively minor in the Eastern, South East and South West regions, given the minor adjustments in seat counts, and these are as it happens all overwhelmingly Conservative areas.  They would, however, be very extensive in Wales, the North West and the North East: all Labour areas (Scotland also would be seriously affected).  Of the Conservative-leaning areas, only the West Midlands would see heavy reorganisation.

The consequence might well be that the bulk of Conservative incumbents could see their incumbency damaged in only minor ways, while Labour incumbents would be much more likely to see their incumbency seriously affected.

It gets worse for Labour.  Many of the constituencies with the lowest number of registered voters are in contiguous Labour-held areas.  On a shrinking seat count determined by numbers of registered voters, that is the worst permutation for a party, because there is much less scope to recoup lost seats in the area by taking seats of a rival party.  Leeds, Bradford, Hull and Liverpool are all stuffed full of constituencies with very low numbers of registered voters, all with large Labour majorities.  If the seat count in those areas is reduced, that will probably come straight off the top of the Labour seat total.

Meanwhile, the smaller parties all get hit still harder because of the consequences of reducing the seat count noted above.

My artist’s impression of how the results of the last election might have translated onto reasonably normal boundaries on the new basis is something like the following:

Conservatives: 316 Labour: 209 SNP: 50 Lib Dems: 5 Plaid Cymru: 2 UKIP: 1 (maybe) Greens: 0 Speaker: 1 Northern Ireland: 16

By this stage, the Conservative majority, now hypothetically 32, is starting to look very solid given the smaller size of the House.  Again, I don’t feel that I have particularly stepped out in one direction or another.

So if you want to see why the Opposition (and the Lib Dems in particular) might seek to block the boundary review, this is why.  Their task is hard enough, without the Conservatives being given a still greater head start.

Antifrank