EVEN by the standards of the neck-deep, decades-long squalor of Tory sleaze at Westminster, Boris Johnson was probably sitting relatively pretty until yesterday morning – at least in terms of the English electorate.

In Scotland, it seems beyond comprehension that a leader could survive the allegations against Mr Johnson. However, the English voters who put him in office knew what they were bargaining for – they knew he was a liar, a cheat, an arch manipulator who didn’t give a damn for honesty and integrity (or "a bit of a lad", as his supporters in the shires might say with a wink).

In some twisted way, that was part of his appeal. So recent events, although ugly, were never going to damage him badly: the Greensill scandal, the Dyson tax texts. To the party faithful, Greensill was just Tories being Tories; and with a bit of cognitive dissonance the Dyson tax texts could be passed off as good old booster Boris bending the rules and doing anything to keep Blighty safe during pandemic. Plus, Mr Johnson had that vaccine bounce to depend upon.

Even the stab in the back from his erstwhile Rasputin, Dominic Cummings, brutal though it was to behold – that the Prime Minister planned to get Tory donors to pay to jazz up his Number 10 flat – was still just about survivable, gross though the claims were; if the base wasn’t going to desert Mr Johnson after the "special treatment" allegations surrounding his apparent affair with Jennifer Arcuri, he’d survive a spat about interior design.

What’s really going to do for him, though, is how the narrative around sleaze has now shifted to Covid. The first glimmers that the sleaze allegations were going to become uncontainable were in Mr Cummings’s blog post last Friday when he spoke of Mr Johnson wanting an inquiry into a leak about lockdown timing shut down because suspicion might fall on a friend of his fiancee, Carrie Symonds. The Court of Johnson certainly has an imperial feel to it, with the partner to the man in power seemingly able to wield unaccountable influence over affairs of state.

Read more: Boris Johnson is Nero, fiddling while Rome burns

That melding of Mr Johnson’s private life with how the nation deals with Covid is instantly much more corrosive in the eyes of the party faithful than the usual cronyist antics of the Tory top team. A few rolls of wallpaper or some schmoozing by David Cameron are one thing – but the idea that Mr Johnson’s love life might in some way interfere with the fight against Covid, or the lessons learned, will overcome even the most stubborn case of wilful blindness within the "Boris Base".

Not that the party faithful should be surprised that Tories were sleazing all over the pandemic – there was a "Crony Express" for pals of the hierarchy which offered special treatment when it came to pitching for Covid contracts. Still, that was about money and big business, not lives lost to the pandemic, and so it didn’t really cut through, much to the bewilderment of those not in thrall to the Johnson cult.

Then yesterday came the old switcheroo – as the vaccine bounce deflated with a headline that changed everything. “Boris: ‘Let the bodies pile high in their thousands’.” Amid the war with Mr Cummings, claims were made that Mr Johnson said he’d rather see mass deaths than order a third lockdown. Downing Street says it’s all a lie.

Dominic Cummings

Dominic Cummings

Mr Cummings isn’t finished yet – he says he’ll pass information to any Covid inquiry, and he’s set to appear before a select committee next month. Evidently, the absurdity of Dominic "Barnard Castle" Cummings sitting atop the moral high ground shows just how rotten this whole affair is – but he knows where the bodies are buried; he’s the gravedigger after all.

As we start to emerge from the pandemic, the public will want answers for what went wrong and why. Any politician caught up in allegations of wrong-doing or deliberate mismanagement or politicisation of Covid will find themselves dipped in acid. Even the most Teflon politician will be eaten alive by public opinion. So Mr Johnson’s future hangs in the balance right now. Who knows if he can survive this? The Tory Party has no problem knifing a leader if they’re seen as a hindrance to power. This is the party which finished off its own "Blessed Margaret" after all.

Read more: The Grensill lobbying scandal

The first real casualty of Tory sleaze and Mr Johnson’s "Cummings War", though, will be found north of the Border in the shape of Douglas Ross. He’d happily rebuild Hadrian’s Wall to keep his leader out of Scotland, but he's now going to have to carry the can for him.

The Tories were set for second place at Holyrood but already polls have changed, putting them in third. Mr Ross’s narrative has been that a vote for the SNP means another referendum – and who needs that at the time of pandemic recovery? You can hear the snorts of contempt already from voters. If anyone is undermining the country at a time of pandemic, it’s Mr Johnson, many will feel – and by extension his branch manager in Scotland. And undecideds may well think: to hell with this, another referendum might be divisive but surely it’s better than that lot down in London.

One issue that will be killed off by the latest chapter of Tory sleaze is talk of a snap referendum called by Mr Johnson after the Holyrood vote to wrong-foot Nicola Sturgeon. Mr Johnson, with his reputation in the gutter even among the perennially-blinkered Tory base of middle England, will be firmly risk-averse.

Ms Sturgeon sees this all as a feast worth savouring. The stink around the Tories makes any allegations of sleaze against her party seem inconsequential. In any inquiry into failings by her Government into the handling of Covid, proof of flawed decision-making and bad management in Scotland will also seem small-time compared to the rot in London.

Only the courageously foolish remain in the business of political predictions after the lessons of Brexit and Donald Trump. So betting on the demise of serial survivor Mr Johnson is for the rash – however, you’d have to be religiously cautious not to hazard a flutter on the unfortunate Mr Ross as the main victim of Tory sleaze, at least for now.

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