‘But We Won’t Be Competing With the SNP.’

Another assertion frequently made by proponents of the new ‘indy supermajority’ list parties (such as the AFI and ISP), is that you can safely vote for them, as they ‘won’t be competing with the SNP, but targeting unionist list seats instead’.

Anyone with even the slightest familiarity with how the Additional Member System (AMS) seats are calculated will know this is patent nonsense.

The list seat allocation process starts with the regional list votes of each party, divided by the number of constituencies already won in that region plus one (the ‘quota’):

This is calculated for each party to determine the first list seat. Let’s look at an actual example from 2016. The nine Lothian constituency results were as follows:

SNP — 6
Labour — 1
Conservative — 1
Lib Dem — 1
Green — 0

Here is how the seats were calculated for Lothian Region at the last election. The starting values are the regional votes cast for each party, and the second row (‘Add Votes 1’) is this figure divided by the constituency seats already won for each party plus one (to avoid a division by zero for parties which have won no constituencies).

It is then simply a matter of seeing which party has the most votes. For the first seat, you can see that this is the Tories on 74,972 votes, therefore they get the first list seat.

For the second seat, the Tory regional list vote is now divided by seats won (now two — one constituency plus one list) plus one. You’ll see that the highest value in the second seat row is for the Greens, therefore the Greens are awarded the second seat.

I won’t inflict the further rounds on you — you can readily identify which party wins each seat yourself — but I would like to draw your attention to the final row where the seventh and final seat is calculated. (This is where parties can easily be pipped to the post for a list seat.)

The votes for each party are now:

Greens — 17,276
Labour — 16,998
SNP — 16,935
Conservative — 14,994
Liberal Democrat— 9,240

In this region, the seventh and final seat thus went to the Greens. But observe just how close the top three parties were.

In this example, you can readily see that it was the SNP, Labour and Greens all pitted against each other for that seat, not a case of indy parties fighting unionists.

If the SNP list vote in Lothian was up by taking only 1.53% of the Green vote (that’s a mere 532 votes), the SNP would have taken that last seat instead of the Greens. That is, if 532 SNP or indy voters were voting ‘tactically’ for the Greens, they did get a Green MSP, but at the expense of the SNP and not the unionists.

Since this example is based on an actual election, we can calculate precisely the swings needed to shift seats about — after the election, with the results.

Obviously, it is impossible before an election to know how close these list seat calculations will be and how the seat allocations will work out (‘we need just 1.6% more support or 532 votes and we’ll win the last list seat…’).

The Lothian example clearly demonstrates how the D’Hondt process simply awards seats sequentially to the party with the highest votes at each stage. All parties are competing against each other: Labour against Tory and SNP against Green as much as the indy parties are competing with unionist ones.

It is thus obviously impossible to target seats of particular (unionist) parties.

Anyone who tells you that you can vote for minor indy list parties in order to ‘target’ only unionist seats either hasn’t the slightest clue how the seats are calculated or is lying to you in order to attract your vote. There’s just no two ways about it.

Let’s look at another example, from the Highlands and Islands, where this time it was the SNP vying with unionists for a list seat in the sixth round.

Remember these are the actual election results from 2016, not projected votes from a poll, so we can precisely calculate the effect on the election result of splitting of the SNP vote in terms of seats won or lost.

In this region, the SNP has enough votes to win the sixth list seat allocated, being just over 200 votes ahead of Labour.

But the fringe party devotees tell us that an SNP list vote is wasted:

Let’s see what would have happened in Highlands and Islands if the SNP vote had haemorrhaged to list parties such as the AFI or ISP.

If as much as 4% of the SNP list vote was split between these fringe indy parties, or even taken by just one of them, this is what would have happened:

Labour would now have picked up that sixth seat from the SNP, and the Tories would now win the final seat! In other words, an SNP seat lost to the Tories.

I can already hear the complaints of the list party advocates: “well, that was a region where the SNP had a seat to lose, what about regions that didn’t have any SNP list seats?”

We’ll examine this presently, but first a very important point has to be made that where the SNP wins list seats comes down to percentage list support. Indy list party devotees seem to imagine that, in 2021, SNP list seats will be won in exactly the same regions as in 2016.

Thus they say that they won’t stand in South Scotland, leaving the impication they will stand in regions that returned zero SNP list seats in 2016, such as Glasgow, where we’re told it is ‘impossible’ for the SNP to win a list seat.

Currently polling, however, predicts just this: SNP winning seats in Glasgow and Central, and losing seats in South Scotland.

However if there is a small boost to the SNP percentage in South Scotland, or a tiny fraction of the Tory vote plumps for George Galloway’s Alliance 4 Unity, the SNP can snatch that last list seat instead of the Tories. So even in a region where the SNP is now projected to win no list seats, but still has the potential to steal one from the Tories on the slimmest of swings, SNP votes lost to fringe list parties can only serve to ensure the Tories keep that seat.

The claim that these list parties won’t be standing in regions ‘where the SNP has list seats’ thus flies in the face of the fact that we cannot know for certain at all in which regions the SNP will win list seats. In many regions, the SNP might just be in with a chance of winning that final list seat. Thus any region where a fringe indy list party stands could see it allowing potential SNP seats to go to the unionists.

In the case of Glasgow and Central, on projections from current polling, if you vote for a fringe list party, you may as well just vote Labour, as potential SNP list seats will be won by Labour instead if enough voters defect.

Let’s now give our attention to regions where the SNP returned no list seats in 2016, and examine the indy list parties’ claim that a vote for them will usher in the fabled ‘indy supermajority’.

Remember, we’re looking at the actual results from 2016, where we can precisely model the effects on the result of SNP votes defecting to indy list parties.

‘2016 Through the Looking Glass’

Let’s have a thorough look at the 2016 election results, and model what would have happened if the unionist and Green vote remained the same, but SNP votes haemorrhaged to small indy list parties.

In other words, imagine if the AFI and ISP had been standing then and were siphoning off votes from the SNP. Presumably, we would see lots of indy wins, as these parties are ‘targeting only unionists’, right?

Here’s the baseline, a summary of where the list seats went in the last election:

(The yellow and blue ‘bloc tracker’ at the bottom presents an each way to see the effects on seat total for both the independence and unionist sides.)

Let’s first apply a 4% defection from the SNP to the list parties.

This reveals what we discovered in our earlier analysis of the Highlands and Islands — this level of defection will see the SNP lose its list seat there to the Tories. Indy bloc one seat down. There are no changes in the other regions.

It then takes a whopping 14% swing from the SNP to the fringe parties (i.e. over 130,000 votes nationally — more than the vote for the Lib Dems) for the next seat to change hands:

Now the SNP loses one of its South Scotland seats to the Greens. No change in the indy bloc, but still one seat down from the earlier loss of the H&I seat to the Tories.

At 22.6% defection from the SNP (215,000 votes), the Tories lose a seat to the stronger list party:

But we are now just back to where we were at the very beginning, in terms of indy vs unionist seats. We are already well beyond any realistic swing away from the SNP, but no sign yet of the fabled ‘indy supermajority’.

So, purely out of academic interest, let’s proceed to shift even more SNP votes to the list parties.

At a 23% swing away from the SNP, the AFI (or whichever), now just takes a seat from the Greens in the West of Scotland. No change from the start.

At a 25% swing, the AFI now just takes the seat from the Greens in South Scotland, which the Greens had previously taken from the SNP:

Again no change whatsoever to the original division of list seats between indy parties and unionists. This ‘tactical voting’ doesn’t seen to be going according to plan at all…

Maybe we just still need to ‘redirect’ even more SNP seats to the indy list parties.

At 26%, the weaker indy list party wins its first seat…from the SNP in South Scotland! But the stronger one takes a Tory seat in North East Scotland:

Finally, with over a quarter of the SNP vote split between these two fringe list parties (almost a quarter of a million votes), the indy bloc is one seat up!

Let’s look at one last example:

Finally, at 27% of the SNP vote defecting, the indy bloc is up just five seats. Hardly a ‘supermajority’.

But there’s other practical considerations to be made too.

Given the completely unknown nature and untested stability of new list parties, would SNP voters really want to cost their party three list seats, meaning that the indy majority would now no longer result from just two parties (the SNP and Greens) but instead now need four parties?

As an SNP supporter, I certainly wouldn’t.

But, of course, this is all entirely hypothetical. No one seriously expects these parties to ‘mop up’ almost a third of the SNP vote, certainly not if they have never yet even registered outside ‘others’ in an opinion poll.

If you don’t want to vote SNP, then a vote for the Greens is the only other sensible choice for an indy supporter, as current polling has the Greens on course to win at least one seat in every region.

RISE and Solidarity

Fringe list parties such as the AFI and ISP didn’t exist in 2016, but RISE and Solidarity did.

What would have been the effect if these parties didn’t stand and all their votes (just 1.1% of the total) had gone to the SNP instead? The only way to find out is to crunch the numbers.

Obviously, their votes would have gone to other parties too (Green and Labour), but let’s just see if it would have made any difference to SNP seats if all the votes given to RISE and Solidarity had gone to the SNP instead.

Here’s the actual result again:

And with all the RISE and Solidarity votes transferred to the SNP, this is the result:

No change from before: the level of support these two parties had was insufficient both to have gained seats, but thankfully also not enough to have cost the SNP seats.


The 2016 election provided a ready made scenario, where we could precisely examine the effect of SNP votes defecting to minor indy list parties on actual results. The outcomes were not encouraging.

In 2021, in the absence of polling showing otherwise, the most likely scenario is that these new minor list parties will similarly fail to put the heather on fire, attracting about the same share of the vote as RISE and Solidarity in 2016 — approximately 1%.

The danger for the SNP lies in the possibility that these parties manage to exceed all expectations and creep up towards 5% — our analysis of 2016 reveals how this can lead to SNP seats being lost to unionists.

But even at higher levels of support, hardly any difference was made to the balance between the independence and unionist blocs, until fully 27% of the SNP defected. In 2016 this would have meant that the ‘indy bloc’ at Holyrood would have needed to have been composed of four as opposed to two parties, due to SNP and Green losses, which would have been more precarious and much less stable an arrangment.

Finally, had anyone still been labouring under the misapprehension that unionist seats can be ‘targeted’, without endangering SNP seats, the review of how regional seats are calculated and the modelled scenarios will have dispelled that notion.

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