The Scottish National party (SNP) is accustomed to presenting Westminster dysfunction as a boost to its case for independence. But the political drama unfolding in London since May’s local elections, culminating on Monday in Sir Keir Starmer’s enforced resignation, has also been welcome for a more discomfiting reason. The glare of the spotlight on Labour’s internal revolution has allowed its own travails to play out in the shadows.

The five-year sentence handed down on Tuesday to the former SNP chief executive, Peter Murrell, brings a form of closure to one of the biggest political scandals in Britain for decades. Scotland’s first minister, John Swinney, has rejected calls for an inquiry into Murrell’s embezzlement of more than £400,000 from SNP funds over a 12-year period. But unanswered questions remain regarding how Murrell got away with stealing from the SNP for so long. The party’s financial probity is also under scrutiny over the use of more than £600,000 theoretically ringfenced for an independence referendum.

As Sir Tom Devine, the historian, has noted, the Murrell affair raises concerns over the internal culture and complacency of a party that has monopolised power in Scotland for two decades. Meanwhile, as Britain’s media descended on Makerfield for the byelection that launched Andy Burnham towards Downing Street, the SNP suffered a wounding loss in Aberdeen South, where the Conservative party celebrated its first Westminster byelection gain in Scotland since 1967.

While Murrell came up on doorsteps, it would be dangerous to draw wider lessons from a contest defined by anger over job losses in Aberdeen’s oil and gas industry. On the same night in Arbroath and Broughty Ferry, the SNP got over the line, benefiting from a split vote between Reform UK and the Tories on the right. But the party’s victory in May’s Holyrood elections was accompanied by little enthusiasm and its lowest constituency vote share since 2007. Amid ongoing concerns over its record on public services, any feelgood factor has gone missing.

Whether the SNP will continue to dominate by default, in a fragmented landscape, may depend on factors outside Mr Swinney’s control. In Aberdeen South, where the decades of drilling in the North Sea have delivered a solid and prosperous Tory vote, Kemi Badenoch’s decision to throw resources at the seat was vindicated by an impressive majority, boosted by tactical voting. But a strident anti-net zero message is likely to be far less popular in much of the rest of Scotland. Polling by More in Common’s researchers has found that, by a ratio of five to one, British voters believe the shift to green energy will “make life better” for people like them.

Scottish Labour’s fortunes, having plummeted as the Starmer government became calamitously unpopular, are likely to depend on Mr Burnham’s ability to reset to the left and convincingly take on Reform. Should he succeed in doing so, the SNP’s ability to position itself as the progressive as well as the nationalist option would be threatened.

Following Murrell’s sentencing, Mr Swinney and his party will now hope to move on. But as it makes an uncomfortable start to a fifth successive term in office, the SNP’s aura is not what it was. Labour is not the only party in need of a period of renewal.

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