BORIS Johnson is the jammiest of beggars. He has in abundance what all leaders crave but few enjoy – luck. Though it may not seem that way given recent and past calamities, consider this: he is still there.

Incompetent, duplicitous, shameless, a failure at a time when his country has never needed effective leadership more, yet he is still there.

This week it seemed as though his luck was beginning to run out. Having bulldozed his way through two Downing Street press conferences; seen his chief aide, Dominic Cummings, stink up Number 10’s rose garden with his own display of obfuscation; had a Minister resign; and defied calls from more than 35 of his own MPs for Mr Cummings to be sacked for breaking lockdown rules, the PM must have thought he was through the worst. Then he checked the diary and found he was due before the Commons Liaison Committee.

Or to give it its oft cited title, “the powerful Liaison Committee”. Made up of select committee chairs, most of them senior MPs, it is the only Commons panel that can question the PM. If he deigns to attend, that is. Mr Johnson has been in power for almost a year, yet every time he has been asked to appear he has discovered something else he would rather do.

Then he got lucky again. Against precedent, the committee chair, usually chosen by members, was instead proposed by the Government and, after some grumbling, accepted. It was another sucker punch to democracy and accountability, but no-one paid that much attention. When you are willing to prorogue a parliament, what’s a little fuss over twisting the arm of a Commons committee? And so Bernard Jenkin MP was installed.

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This was a chance for MPs to get clear answers on the now infamous dash to Durham, and the subsequent trip to Barnard Castle, again in defiance of lockdown rules. How could the PM justify keeping his aide on when he had breached the regulations other people, often at great personal sacrifice, had abided by?

A grand parliamentary occasion, then, with no danger, as in the daily, increasingly farcical Downing Street briefing, of muting the inquisitor if you don’t care for the question.

What did we get? More shameful bluster and muddle. Another chance to examine that brass neck of his in grisly detail. Labour’s Yvette Cooper and the SNP’s Pete Wishart took decent swings, but it was like boxing with a water bed.

Mr Johnson either does not get it or he does not care.

There is a part of me that wants to thank Mr Cummings for doing us all a favour. It is a feeling I have admittedly wrestled with, my own personal “Shall I drive 60 miles in a fast-moving lump of metal containing my wife and son to see if my eyesight is dodgy?” test.

Yet has acted in the best interests of the country in one sense. Sure, he has undermined his own guidance, made millions of people feel like prize mugs, and possibly left the door open to a mass flouting of social distancing rules that will increase the already obscene number of deaths in this country – largest in Europe, remember. Yes to all that.

But he has also drawn a moral line in the sand, one so obvious you can probably see it from space. Instinct dictates which side you are on. We have heard a lot this week about instincts. When Mr Cummings drove his family 250 miles to Durham, despite his wife displaying Covid-19 symptoms and fearing he was about to fall ill as well (how clever of him to know he would make it to Durham without passing out), the PM said his aide had “followed the instincts of every father and every parent” and he “did not mark him down” for that.

So when the rest of us followed the mantra: “Stay home, protect the NHS, save lives”, Mr Cummings, with his bigger brain, heard: “Follow your instincts, do what you like, we’ll sort it out later”.

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As it turns out, Mr Cummings, as so often in his life, has been a trailblazer. If we follow our instincts, our primary sense of right and wrong, our gut feeling, then it is obvious that Mr Cummings should resign. If not for the original trip to Durham then definitely for the castle adventure. If not for that, then for the fact that he has shown no regret and made no apology.

The same clear line applies to Mr Johnson’s actions. If you think he was right to stand by his man and not sack him, stand on that side of the line. If you think he was wrong, head over there. Simple. Child’s play, even.

The line is so obvious, and the choosing of a side so straightforward, then the next step, if we are following our instincts, is to judge people according to their choice. So bravo to Douglas Ross, Tory MP for Moray, for taking a stand and quitting as a Minister. No cheers, however, to the party’s Scottish leader, Jackson Carlaw, who went all round the houses before eventually saying that while he was not going to tell the PM what to do, if he was Mr Cummings he would be considering his position. Nothing like clear leadership, eh?

This choosing of sides is liberating. So often in politics matters are complex, there many shades of grey. At a stroke, Mr Johnson and his aide have cut through the fog.

Yet there is a downside to this break in the weather, one that has profound implications for us all. If Mr Cummings stays in his job, despite everything, then his bad behaviour becomes “the new normal”.

Ditto, if Mr Johnson does not sack him, it will have become accepted conduct for a Prime Minister not to answer direct questions, and to turn a blind eye to rule breaking. All notions of decency in public life will be up for negotiation, the rule book, written and unwritten, not worth a jot. What a dangerous, depressing path that takes us down.

It has been two months now since Emily Maitlis’s documentary, Taking Control: The Dominic Cummings Story, was shown on the BBC. In it, Peter Mandelson,who could only dream of the prime ministerial support Mr Cummings has enjoyed, said of the PM’s adviser: “He could just completely blow himself up, but if he doesn’t he’s going to be a very significant figure over the course of the next ten years.”

A line has been drawn. Which side are you on?

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