So here’s a thing. Last week a prominent defence lawyer broke ranks and declared that the police investigation into alleged misuse of SNP party funds – Operation Branchform – had been going on too long and should be wound up pronto. Scottish criminal defence lawyer Thomas Leonard Ross KC told Sky News the probe ‘cannot go on indefinitely’. ‘Once somebody is charged then they have the right to a trial within a reasonable time,’ he said.

Many Scottish politicians have been saying this privately too – not all of them nationalists. Then, by a remarkable coincidence, the Sunday Mail revealed exclusively this weekend that ‘prosecutors investigating SNP fraud allegations are examining evidence that a fake firm received payments for refurbishment work carried out on the party’s headquarters’.

If true, this is far, far worse than Boris Johnson’s wallpaper or Keir Starmer’s costly specs

Here we go again. This is a brand new twist to the longest-running true-crime mystery in British politics. Police Scotland are now allegedly investigating £500,000 worth of embezzlement, with £100,000 spent on the HQ refurbishment alone.

If true, this is far, far worse than Boris Johnson’s wallpaper or Keir Starmer’s costly specs. No one accused them of involvement in embezzlement.

I’m sure the police could not possibly have been the source of this leak since that would open them to accusations of media manipulation. However, we have had curiously-timed revelations about Operation Branchform for the last two years at least.

Remember those pictures of the £110,000 Niesmann and Bischhoff campervan being driven away from the former SNP chief executive, Peter Murrell’s mother’s Dunfermline home in April 2023? Then there were the stories in the press about everything from kitchen knives to a fridge freezer being investigated by police following a raid on the SNP headquarters in Edinburgh. Had the nationalists been trying to run a department store, we wondered.

But, of course, the police don’t do this kind of leaking of evidential details. This could compromise any court case against Nicola Sturgeon’s husband, the same Mr Murrell who was charged with embezzlement of party funds in April. Murrell denies any wrongdoing. We’re told that a 53-year-old woman and a 72-year-old man are still under investigation. That would be Ms Sturgeon and the former SNP treasurer, Colin Beattie who were arrested and questioned in 2023 and released without charge. Sturgeon and Beattie also deny any wrongdoing.

To say that the SNP is furious about this long-running stain on their party’s character would be an understatement. Many believe that the SNP’s fall from grace is a direct consequence of this eternal police investigation. Polling guru Sir John Curtice agrees and says that Operation Branchform certainly contributed to the SNP’s catastrophic general election results. It wasn’t the only reason the SNP lost 38 seats, of course. NHS waiting lists, unpopular green policies and rapists in women’s jails also wrecked public support. But the drip drip of damaging fraud-related revelations has been a PR disaster.

These stories about the party began appearing not long after the nationalist activist Sean Clerkin first complained to the police in 2021 about the alleged misuse of £660,000 in donations collected for an independence referendum that never happened. For most of the ensuing two years the SNP leadership thought this was a silly stunt from an attention-seeking ‘heid-the-baw’ that would go precisely nowhere. After all, the SNP is dedicated to securing Indyref2 in every manifesto, so surely any money donated for that purpose could reasonably be used for general party expenditure at election time.

As Operation Branchform dragged on, SNP figures like Sturgeon’s former special adviser, Noel Dolan, went public calling the police investigation ‘completely over the top’. Murray Foote, the former SNP communications director, called it a ‘wild goose chase’. That was in the spring of 2023. In August that year, the retiring chief constable of Police Scotland Sir Iain Livingstone went on the Today programme with the bombshell that the police were now investigating complex issues relating to fraud and ’embezzlement’.

The use of the ‘e’ word shocked critics into silence. The press had already been warned not to indulge in idle speculation about Operation Branchform unless they wanted to be hauled up for contempt of court. But it took a year after Livingstone’s intervention for Peter Murrell to be actually charged. Just in time for the SNP’s general election election campaign.

Police Scotland handed the case to the Crown office in August. It’s time for the prosecutors to put up or shut up this endless legal imbroglio.