IT is one rule for us, another for them. There is – after nearly two years of a deadly and economically crippling pandemic – something raw and powerful about this simple idea.

In London, the regime of a vulgar, populist, nationalist premier is tottering as it emerges he and his officials shrugged off the Covid restrictions they imposed on others.

And for what? Only, the latest revelations suggest, to slug supermarket wine in a garden. It is all, for want of a better word, a bit pathetic. But also politically potent.

Boris Johnson’s parties, those indefensible, incomprehensible parties; they hurt. Think of the way the voice of Northern Ireland MP Jim Shannon broke up as he tried to ask the prime minister about ongoing investigations in to No 10 knees-ups. Remembering how his mother-in-law died alone, the DUP man could only squeak.

READ MORE: Salmond inquiry: Saga is a 'disinformation event'

Social media first simmered with emotions, then boiled. There were people who were angry and people who were sad.

And there were people who, well, lied.

That is because these Partygate stories – albeit revealed by mainstream, regulated print and broadcast journalism – create a perfect storm for disinformation. As does any news which provokes a powerful emotional response. It gets clicks, likes, shares, retweets.

Evidence-based news media allegations about Mr Johnson sparked furious calls for his Scottish counterpart to answer for her alleged “one rule for us, another for them” behaviour.

Why, largely anonymous social media accounts spat in to the ether, was Nicola Sturgeon not being held to account? The first minister, they said, had been holidaying in Portugal when she asked punters not to booze in England at Hogmanay.

Except, no, she had not.

This was just something somebody had made up on the internet. It was, said the Scottish Government, “untrue”.

There is nothing new about online conspiracy theories featuring the SNP leader – many of which are too absurd and offensive to repeat here. Twitter – and, increasingly, the US far-right platform Gettr – brim with such nonsense.

READ MORE: The war on disinformation

The latest make-believe is quite elaborate, with anonymous social media users sharing flightpath maps for a private jet from the Algarve to Glasgow. There was no reason to think the first minister was on board, or that she somehow contrived to construct a facsimile of her St Andrew’s House HQ in Portugal for virtual public appearances.

It would take somebody far smarter than me to explain what is happening in the brains of the kind of radicalised, gullible hyper-partisan who takes this stuff seriously. But they are among us, our neighbours, our friends, our family.

There has long been angst among serious unionists about their counter-productive internet fringe. Usually this concern focuses on abuse, most recently aimed at linguistic minorities. But “very online” pro-UK extremists in Scotland, in my view, pose a bigger threat than being rude, chauvinistic or obnoxious. They are, to be blunt, a disinformation risk.

Their sheer gullibility, their readiness to believe almost anything negative about their opponents, is dangerous. And also unnecessary: after a decade and a half of power it is hardly difficult to fault find with SNP ministers without spreading fairy tales.

There are some cyberyoons – to use derogatory internet shorthand – who now inhabit an alternative online reality.

Worse, some of the more radicalised British nationalists have started wading in a global cesspit of disinformation, which includes toxic culture war narratives about everything from race to pandemic responses.

The recent switch to Gettr – something that some online Scottish nationalists have also done – is concerning. This self-styled “free-speech” platform is where US extremists, such as conspiracy theorist congresswoman Marjorie Taylor Greene, have fled after being banned by Twitter. It is a sewer.

Dysfunctional political social media accounts are hardly new. Neither are attempts to deal with them. It is now nine years, for example, since senior SNP activists made their first concerted attempt to talk down so-called cybernats, who, apart from their flags, are largely indistinguishable from their unionist counterparts.

Calum Cashley, an amiable party staffer who died last year, set the tone by challenging a Twitter account demanding English-based people should not be allowed to comment on Scottish BBC stories. How successful was this? It is hard to say. Chunks of the very online fringe of Scottish nationalism have now splintered away from SNP.

Earlier this month, almost unnoticed, there emerged a sort of unionist Calum Cashley.

Blair McDougall, the man who led the campaign to keep Scotland in the UK, published an eloquent and eminently sensible appeal for those opposed to independence to behave online. He railed against misogyny against Ms Sturgeon, against hyperbole, and against the culture of “shooting at the referee” – by which he meant abusing journalists.

Social media, he wrote in his Notes on Nationalism newsletter, “gamifies political division”; its users became addicted to antagonism and forgot the point was to win arguments, not have them.

“If you recognise some of the behaviour above in people you interact with online, challenge it,” Mr McDougall concluded. “If you recognise it in yourself, reading this might make you angry. So be it. But you need to understand that these behaviours make the break up of the UK more, not less likely.”

We should all welcome efforts by campaigners such as Mr McDougall or the late Mr Cashley to police their own sides, even if doing so is a political tactic. But we still need to watch out for those who insist disinformation is something the other side does or says – while indulging it on their own. Because if there is one thing that really gets under our skin, it is when there is one rule for us, and another for them.

Our columns are a platform for writers to express their opinions. They do not necessarily represent the views of The Herald.