The SNP continues to dominate Scottish politics. The party’s recent polling figures would be the envy of any party and are remarkable for a party that has been in government for more than 15 years.

The most recent Ipsos poll (conducted in December 2022) found around half of likely voters say they would vote for the party in an immediate General Election – although of course a General Election is still some way off, with the next vote unlikely to take place until 2024. Recent polls all continue to show SNP support far ahead of support for its closest rival among voters, the Scottish Labour Party.

The party’s continued strong standing among the electorate is far from the only positive news for the SNP from recent polling. Eight years into her tenure as First Minister, Nicola Sturgeon remains the most popular of the Scottish party leaders among the public, although satisfaction with her performance has slipped back slightly since May.

Support for an independent Scotland has also risen, in the wake of October’s Supreme Court ruling that the Scottish Parliament cannot legislate for a second referendum on independence without Westminster consent. Four successive polls have shown Yes in the lead, although it remains to be seen whether this is a temporary bounce or a longer-lasting trend.

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Beyond these positive headlines though, there are warning signs for the party. Trust in the SNP to manage public services and the economy has fallen considerably over the past 18 months, according to Ipsos’ polling trends. Fewer than half of Scots now say they trust the party to deal effectively with managing the NHS, down 18 points since April 2021. Moreover, half don’t trust the party to tackle the cost of living crisis in Scotland. These perceptions matter, since these issues are also the top two concerns on the Scottish public’s minds.

This criticism of the SNP’s performance on what – according to the public – are the most important issues facing Scotland might reasonably be expected to lead to a decline in support for the party. The paradox is that while people have become more critical of the SNP’s performance in government, this doesn’t seem to be denting the party’s electoral prospects. Half of those who would vote in a Scottish Parliament election say they would cast their constituency vote for the SNP, if anything slightly above the 47.7% who actually used their constituency vote for the party at the May 2021 Holyrood elections.

Why aren’t we seeing a slump in voters’ support for the SNP, since public trust in the party’s competence has declined? The key factor shoring up SNP support appears to be people’s views on the constitutional question. Support for the SNP is now very closely correlated with support for independence, with 84% of those who would vote Yes in an immediate referendum on Scottish independence also saying they would vote SNP in an immediate General Election. This relationship between intention to vote for the SNP and support for independence is even closer now than it was previously.

The Herald: A man walks past a Yes poster in GlasgowA man walks past a Yes poster in Glasgow (Image: free)

When it comes to factors that shape voting intention, SNP supporters’ views on independence appear to be taking priority over their perceptions of how the SNP is actually performing in government. Almost one in five SNP supporters do not trust the party to deal effectively with managing the NHS in Scotland, but they nonetheless say they would vote for the party.

Regardless of buoyant voting intention figures, these are difficult times for the SNP. Recent infighting within the party at Westminster has been widely publicised. With the constitutional question so central for voters, however, disunity may not be as damaging for the SNP as might otherwise be expected.

The party’s leadership also faces challenging decisions about what route to pursue now to try to secure a second referendum on independence. One option mooted by Nicola Sturgeon is for the SNP to fight the next General Election on the single issue of independence, treating it as a ‘de facto’ referendum.

This would be a risky strategy and raises many questions, including whether the outcome would be viewed as a mandate for independence. On recent polling evidence though, this strategy looks unlikely to dent the SNP’s share of the vote. If anything, recent Ipsos polling indicates that framing the vote in this way could slightly nudge up the SNP’s vote share and could see the combined vote for pro-independence parties get over the 50% threshold being proposed as a ‘mandate for independence’.

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Whatever the eventual strategy, an important question is whether the fall in trust in the SNP’s competence poses a risk to the party’s standing among Scottish voters. Will the pattern of voters’ views on the constitutional question eclipsing the dissatisfaction many feel with the SNP’s performance in government continue – or could distrust put some off voting for the party in future elections?

A look at which groups are less likely to trust the party on key public services such as the NHS now than they were previously provides some clues. While trust in the party to manage the NHS has slipped back among all demographic groups in the past 18 months, it has fallen most sharply among working class voters, the under 35s and women.

Young people are the most likely of any age group to support independence, and for this group, the constitutional question may well continue to eclipse any dissatisfaction with SNP performance. The story may prove different for women and working class voters, however. On the evidence of recent polling, women are a little less likely than men to support Scotland becoming an independent country, while working class voters are divided on the issue.

If the SNP does adopt a strategy for independence which requires a majority of voters to vote for the party – or for pro-independence parties – at a future election, maintaining its current strong support will be critical. Even a relatively small decline in electoral support could make the difference between majority and no majority.

If perceptions of the party’s performance slip further among key groups of voters, competence may turn out to matter after all when it comes to the party’s prospects of a route to Scottish independence.

Dr Emily Gray is managing director of Ipsos Scotland