NICOLA Sturgeon’s position is being “jeopardised” by allegations that her allies plotted against Alex Salmond, one of her former special advisers has warned.

Campbell Gunn said the First Minister was being damaged by almost daily claims of “murky goings-on behind the scenes” that led to sexual harassment and criminal charges being laid against her predecessor.

Mr Gunn said Ms Sturgeon should stop blocking evidence to the Holyrood inquiry into the Salmond affair and opt for full transparency instead, even if that meant casualties.

He said: “The remedy is simple and straightforward. 

“Avoid the drip-drip of allegations over a long period of time, by getting everything – whether damaging or not – into the open immediately.

“Take the short-term hit for long-term gain. If that means one or two people are forced to resign or are sacked by the first minister, then surely that’s what has to happen.”

Mr Gunn was a spindoctor to both Mr Salmond and Ms Sturgeon, but has remained closer to Mr Salmond, accompanying him to court at key moments.

He makes his comments in a new article for the Courier newspaper.

A cross-party Holyrood inquiry is currently investigating how the Scottish Government botched an in-house probe into sexual misconduct claims against Mr Salmond in 2018.

The former First Minister overturned it in a judicial review by showing it had been unfair, unlawful and “tainted by apparent bias”, because the investigating official had been in prior contact with his two accusers, contaminating the whole exercise. 

The blunder left taxpayers with a £500,000 bill for Mr Salmond’s legal costs.

Immediately after the collapse of the Government’s case in January 2019, Ms Sturgeon told MSPs any future inquiry “will be able to request whatever material they want, and I undertake today that we will provide whatever material they request”. 

However her Government has since refused to hand over swathes of evidence related to the judicial review by asserting “legal privilege” and tried to stop witnesses from testifying.

Shortly after Mr Salmond won his civil action against the Government he was charged with sexual assault, leading to a criminal trial this year at which he was acquitted on all 13 counts.

His supporters claim the two cases are connected, and Mr Salmond was the victim of a plot to discredit him and stop him making a comeback and rivalling his estranged successor.

The Holyrood inquiry has now become a catalyst for leaks, claims and counterclaims between the rival Salmond and Sturgeon camps within the SNP. 

Former Justice Secretary Kenny MacAskill recently revealed he had received WhatsApp messages sent by Ms Sturgeon’s husband, SNP chief executive Peter Murrell, which appeared to show him encouraging police and prosecutor action against Mr Salmond.

Mr MacAskill, the MP for East Lothian, said Mr Murrell should be suspended as the SNP’s top official.

However the party has taken no action, with its ruling body so far denied an opportunity to discuss Mr Murrell’s messages.

The Crown Office has also instructed the police to investigate the leak of the WhatsApp messages in case they came from material disclosed to Mr Salmond’s trial defence team.

In his Courier article, Mr Gunn said Watergate, the Dreyfus affair and other scandals showed it was invariably the cover-up, rather than the sin, which brought down politicians.

He wrote: “No-one wants to see Scotland head for independence more than me. And I firmly believe that Nicola Sturgeon is, by a distance, the best person to lead us to that goal.

“But her position is being jeopardised by the almost daily allegations that there were murky goings-on behind the scenes that led to the sexual harassment and criminal charges being laid against Alex Salmond.”

He suggested Scottish Government officials, including Permanent Secretary Leslie Evans, has given the inquiry improbable and misleading evidence.

While Mr Salmond, after offering to hand the inquiry swathes of evidence relevant to its work, had been warned off with a threat of prosecution.

Mr Gunn also criticised deputy First Minister John Swinney for a belated and underwhelming offer of getting more evidence to the committee after months of refusals.

He said: “Continued leaks, along with information that has the appearance of being unwillingly dragged out of the Scottish Government, do not help.

“Far better to give the parliamentary committee all the documents, emails and messages currently being withheld and allow it to get on with doing its job.”

He said that if it were not for the coronavirus crisis, the Salmond affair would be front page news, and if Covid recedes from the headlines, the inquiry will be far more prominent. 

“The danger for the Scottish Government is that the Salmond inquiry and the emergence of new and damaging revelations could continue for months, perhaps beyond the end of the year.

“By that time, Covid will hopefully have receded and the media’s focus may well return to the Salmond affair. So, here’s a piece of free advice from a former adviser.

“The solution for the Scottish Government is clear. Don’t cover up. Get everything out in the open. Take the inevitable media hit. 

“It will last only a few days or a couple of weeks, instead of months.

“If the revelations result in one or two people losing their jobs, that must surely be a political price worth paying.”