NOT sure about your approach, but my reading habit is to keep a relatively light book and a substantial work on the go at the same time, varying my nightly choice according to whim.

My current light choice need not trouble us. The weighty tome newly by my bedside is Roy Jenkins’ biography of Gladstone. Having absorbed Jenkins’ fine profile of Churchill, I look forward to his verdict on the Grand Old Man of Liberal politics.

Thinking of Gladstone inevitably makes me ponder upon his great rival, Benjamin Disraeli. It is said that the Tory leader, Victoria’s favourite, once advised a waverer: “Damn your principles! Stick to your party.”

It would seem there are a few Dizzy rascals in the ranks of Westminster Tories right now.

Politics in the 19th century was decidedly robust. However, it is now asserted that the tactics adopted by adherents of Boris Johnson have exceeded anything from the Victorian age.

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Incidentally, I say “adherents” advisedly. There are relatively few avid admirers. Most are going with the flow, prepared to dump the PM at a moment’s notice, should next week’s report into Downing Street parties prove adverse.

It is said that Tory MPs who might have been tempted to submit a letter of no confidence in the PM have been advised, bluntly, to cease and desist.

They have even supposedly been told that key potential investments in their constituencies might be withdrawn if they persist in their criticism. This, it is said, is blackmail.

The pedant in me (I keep it well hidden) notes that, strictly, such suasion should rather be described as intimidation.

Blackmail would be threatening to disclose what the member got up to in Strangers’ Bar on Tuesday night or what took place on that cross-party trip to Cyprus. Perhaps the BoJo adherents have such tactics in reserve.

It has frequently been claimed that the party Whips offices in the Commons keep little black books of misdemeanours, ready for emergency use when one of the flock appears intent on straying from the official line.

Perhaps lockdown has deprived them of fresh material or they feel that moral blackmail might be something of a wasting asset when deployed in support of the PM. Either way, it is said they have resorted to less subtle methods.

The complaint was raised by a senior Tory MP, on behalf of others. But comment spread widely. The Speaker, Sir Lindsay Hoyle, stressed that Whips were not above the law of the land.

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Nicola Sturgeon sought to anchor the controversy in Downing Street. She said that such “blackmail and intimidation” pointed to a “moral decay” at the heart of the Johnson administration.

Certainly, it exposes a degree of desperation. Boris Johnson is in grave trouble. Possibly terminal, indeed. He knows that and is reacting accordingly.

Older Commons hands (I worked there as a lobby correspondent during the Thatcher years) will reflect that persuasion by the Whips is scarcely new.

Remember the origin of the term. From hunting (what else). A reference to the role of the “whipper-in”, designed to prevent the dogs from straying too far from the pack.

Tactics in the past might include promises (a better office; yes, some are that petty). Or threats: see yourself as a Minister? Think again!

Strictly, Whips are servants of the Royal household. For example, Alister Jack, the Scottish Secretary, was formerly Lord Commissioner of the Treasury, responsible, as were his fellow Tory Whips, for securing Supply (or cash) for the Crown through votes in the House.

In these less regal days, the Whips’ role is to get Government business through both Houses. They are the silent service. Tory Whips are like prefects or the Officers’ Mess. On the Labour side, in the past, they resembled shop stewards, of the muscular variety.

Remember too that the Prime Minister does not employ his back-benchers. Their job and thus their mandate comes – or should come – from their constituents. Hence, the PM’s minions cannot order or dismiss an MP; they must cajole.

But this affair is different. This is not about securing the Tory Government’s programme from attacks lodged by the Opposition. This is, solely, about saving the skin of the Prime Minister from wounds which are entirely self-inflicted.

To be quite clear, I am not remotely defending the rough-house tactics deployed by Whips Offices in the past. I am simply explaining why they arose, in the absence of direct control. And, further, explaining why this episode is even less defensible.

It is why Nicola Sturgeon felt it credible to call out endemic “corruption” attending upon the PM.

She broadened that attack to include Westminster politics more generally, lampooning Labour for cheerfully welcoming Christian Wakeford as a defector from the troubled Tories. It meant, she said, that both parties were identical.

Not sure that one quite runs its course. Although Ms Sturgeon’s generic rejection of the entire UK was perhaps visibly assisted, for her supporters, when the bold Wakeford subsided on the Labour bench, wearing a bright Union Jack mask.

The defection itself is faintly risible. Mr Wakeford says now that Mr Johnson’s leadership is intolerable.

Exactly what did he think he was promoting to the people of Bury South when he won the seat in 2019? On a Tory platform led by the very same Boris Johnson, whose virtues and flaws were then amply manifest.

A rather more significant role is now afforded to those who remain in Conservative ranks at Westminster. Including, as some have noted, new boys and girls who entered the House, like Mr Wakeford, in 2019 and, owing to Covid, have yet to become inured to its ways, means and foibles.

We all await a solemn report, would you believe, into drink and merriment at Downing Street. Of course, it is more sharply focused than that.

It is about the credibility of the Prime Minister, about trust in his character. Is he, in short, congenitally averse to the truth?

Disraeli declared that he had “climbed to the top of the greasy pole” in politics. Tory MPs now have to decide whether it is time for his successor to slither back down to the ground.

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