The ancient Roman principle of quæ operiat asinus tuus (to cover one’s arse) is also a revered one in the conduct of UK politics.

A slightly updated form is sometimes manifest in the practice of burying bad news, although the dark arts of political manipulation were probably perfected by Quintus Tullius Cicero, the Roman statesman. Cicero wrote an essay about it in 64BC, which was essentially a self-help guide for his older – and better-known – brother, Marcus, on how to get into the senate. In it, he urges his brother to make elaborate electoral promises he had no hope of keeping.

If it were to be revealed that this was one of the favoured texts of the Latin scholar, Jacob Rees-Mogg, few would be surprised. Indeed, Rees-Mogg and his band of arch-Brexiters seem to have gone further than Cicero jnr. They already stand accused by Donald Tusk, president of the European council, of selling Brexit without a plan and by many others of making empty promises, such as those appearing on billboards all over the country. It’s also clear they’ve been softening up the electorate with convenient scapegoats in the event that the entire shadowy enterprise goes in manu cart ad infernum.

Chris Grayling, the transport minister, has already begun to blame EU intransigence for the stalemate over the Irish backstop. This is a bit like the former Wimbledon FC hard man Vinnie Jones blaming opponents on the football field for deliberately trying to dislocate his foot with their testicles. Last week, sources among the Scottish Tories at Westminster elected to blame Brexit for the reported misconduct of their colleague Ross Thomson in the Strangers’ Bar at Westminster. An allegedly drunken Thomson was apparently ejected under police escort following claims of “sexual touching” involving some fellow imbibers, which he has since denied. “The stress of Brexit was getting the lad down” was effectively the response of some in Scottish Tory circles.

The next day, Police Scotland said it was establishing a task force of 360 riot police in the event of civil disorder after the UK leaves the EU on March 29. The timing of the announcement was perhaps unfortunate and any concerns about outbreaks of inappropriately amorous attention at ports and harbours can probably be allayed.

To be fair to the Scottish Tories, Jackson Carlaw, the former car salesman who is now the deputy leader of the party at Holyrood, moved quickly to address the allegations seriously by stating that there would be an investigation. Nevertheless, I feel that the initial instincts of some of his colleagues in blaming “the stress of Brexit” will become a familiar refrain.

You can virtually guarantee that the entire community of UK asset-strippers will be rehearsing the “blame-it-on-Brexit” routine for taking down previously buoyant businesses. “Yes, I know that Jimmy’s Power Tools had been trading successfully for 150 years before we took over and yes we did max out all the company credit cards and banking credit facilities, but Brexit presented us with adverse and unforeseen trading conditions and so we’ve had to go into liquidation.”

Facebook Twitter Pinterest ‘Jacob Rees-Mogg and his band of arch-Brexiters already stand accused of selling Brexit without a plan.’ Photograph: Facundo Arrizabalaga/EPA

Assorted Scottish international football managers have a ready-made excuse for all our future failings in this arena and one with which the public will have sympathy. “The players have all been suffering the stress of Brexit and have been unable to perform at their best.” Expect European referees to become the subject of righteous Scottish indignation when comes the annual mass exodus of our club sides from Europe in the autumn. If I were the sports editor of one of our Brexit-supporting tabloids I’d be seeking a story that purports to expose a Uefa plot to punish all British football teams in Europe with dodgy refereeing decisions. The UK’s annual entrants in the Eurovision Song Contest have actually been using this defence for the last few years.

Enterprising law firms all over Scotland and the UK will be finessing special Brexit defences for when they come to be representing clients accused of unruly behaviour at the weekend. “My client, who as the court must know is of previously good character, has seen his life spiral out of control since the events of 29 March, m’lud. The pillars of the EU upon which he had constructed his entire moral framework are no longer there to provide purpose in his life and he now throws himself upon the mercy of the court.”

In Glasgow, a new phrase will enter the city’s voluminous lexicon of drinking locutions. Thus drinkers will become howling with the Brexit juice or otherwise intend to get absolutely Brexited out of their skulls. “M’lud, the accused was found slumped in the driver’s seat, with a strong smell of alcohol emanating from him. Zadok the Priest, which m’lud might know better as the Champions League theme tune, was blaring from his in-car entertainment system.”

Police Scotland has never been known for a softly-softly approach to dealing with some sections of the community, as the family of Sheku Bayoh, the Sierra Leonean man who suffered a violent death in police custody in Kirkcaldy after being apprehended by up to 11 uniformed officers, can attest to. Can the Scottish legal system be trusted to deal fairly with violent incidents involving foreign nationals or will they apply their own in-house Brexit defence?

• Kevin McKenna is an Observer columnist