YOU can build up a substantial pension pot over two decades of belonging to Scotland’s party of government or travelling along on its coat-tails. In the course of this stretch an entire class of advisers and spinners has flitted here and there between government and handsome sinecures in the private sector. Yet, as another year passes with no immediate prospect of a second independence referendum and no opposition worth the candle, do the earthly blandishments of mere power begin to corrupt from the inside? Thus, might petty jealousies and internal feuds which had all been subsumed in pursuit of a common cause return with a vengeance?

Perhaps it’s in this context that we should view the current tawdry attempts to smear the reputation of Joanna Cherry QC, the SNP’s formidable Justice and Home Affairs spokesperson at Westminster. There is little doubt that this is an orchestrated campaign that reaches into the upper branches of the SNP’s senior management team at Holyrood and Westminster.

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Fortunately for Ms Cherry, accusations that she has permitted a culture of bullying to take root in her parliamentary office will be considered by the Westminster authorities, rather than by her own party. Are these sincere and valid complaints or merely the result of thwarted ambition and hidden agendas manipulated by some of Ms Cherry’s senior colleagues and fuelled by envy? Two of the SNP’s most senior Westminster figures colluded in an attempt to have a complaint made about her heard under the disciplinary procedures of the party rather than the parliamentary authorities. It was clear that these individuals felt there was a greater chance of fitting her up for a fall in these circumstances.

Something rotten has been allowed to fester at the heart of the SNP’s Westminster group and has remained unaddressed for several years. Some who attended the SNP’s group meeting on Tuesday night witnessed at close quarters the loutish results of this. A diligent and well-liked backbench MP was publicly filleted and rebuked for making an unwelcome intervention regarding staff workers briefing against MPs. It was described to me as “an incident of bullying in front of 18 witnesses”.

Ms Cherry warned the SNP parliamentary group about the effects of such behaviour in a letter to Patrick Grady, the SNP’s chief whip at Westminster, written in December 2017. She wrote: “According to recent research by Amnesty International I am the second most abused female MP on Twitter. I did not think I would have to face similar unpleasantness from within my own party.

“During this parliamentary term I have been the victim of behaviour designed to bully, intimidate, discredit and marginalise me within the Westminster group. On two occasions within the last month two senior male members of the group have shouted at me in front of other MPs and staff members in response to my raising legitimate points about the group’s strategy.”

The letter warns the chief whip that she will “do whatever is necessary to protect my reputation … whether by way of breach of confidence or defamatory statements about me being put into the public domain.” Ms Cherry’s concerns were ignored. This week a private and hand-written letter sent by her to another party colleague found its way into the hands of some journalists in the Westminster lobby in a clumsy attempt to ridicule her.

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This campaign seems to have begun after Ms Cherry challenged Mr Blackford for leadership of the Westminster group. She got within one vote of defeating him and panic subsequently ensued amongst Mr Blackford’s closest allies when it was thought (wrongly) that Ms Cherry was set to make another tilt at the Westminster leadership the following year.

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It’s also understood that when Ms Cherry joined Andy Wightman, the Green MSP, as co-petitioner in the case about revoking Article 50 considerable opprobrium was heaped upon her by the Scottish Government. They insisted the case was not part of their strategy and that they saw no value in this. Yet, this is now a central plank of the SNP Brexit narrative.

When the Commons came to consider the indicative votes on both occasions among the small number to be actually voted upon the Speaker, John Bercow selected Ms Cherry’s motions. This would have ensured that revocation of article 50 replaced No Deal as the default position. The sound of teeth grinding was not confined to the Tory benches.

Some have sought to view the campaign to take down Ms Cherry within the framework of a bigger one to purge the party of its strong pro-Salmond faction. This, though, is mere speculation as is the view that Ms Cherry may be positioning herself as a future successor to Nicola Sturgeon. Those close to the front-bencher say she has never coveted that job. In any case the First Minister remains the party’s biggest asset and the one best-placed to bring peace to a situation that is rapidly dragging her party down. Ms Sturgeon might also be advised to address the vicious campaign against those in her party who have urged caution about planned reforms to the Gender Recognition Act which seeks to permit people legally to “self-declare” their gender.

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There is also a lingering sense of anger in the wider Yes community at comments made by three of the party’s grandees last week in which the so-called cybernats were disparaged with words like ‘weird’, ‘creepy’, ‘snarling’, ‘vicious’, ‘poisonous’ and ‘vile’. Ironically, this vivid lexicon is probably a more fitting description of the atmosphere inside the SNP’s Westminster group.

The tens of thousands who have been marching for independence across Scotland in the last year fondly imagine that all of their elected representatives are in this together with them. They deserve much more than to be betrayed like this. It’s now time for Nicola Sturgeon to deal decisively with it. She could begin by reviewing the leadership of her utterly dysfunctional Westminster group as a matter of some urgency.

There has never been a bigger chasm between the SNP’s senior executive and the rank and file of the wider Yes movement. If Ms Sturgeon fails to bridge this it will signal the end of her independence dream.