It is good to see a bit of passion back in British politics. Too often, these days, our elected representatives come across as a collection of devious, underachieving middle managers, unfettered by principle and unmoved by the issues on which they vote. So it was heartening to see the real fervour and commitment in last Thursday’s debate, when our MPs courageously voted to give themselves lots more money and keep their extremely generous expense allowances. That took some guts.

The entire country may be appalled that we pay for MPs’ kitchens, gardening bills, furniture, nannies and mortgages – but, in a sense, that is the true test of the principled man: to stick to your guns, no matter how unpopular that position might be, no matter how much flak comes down.

So the next time some cynic says to you, in that lazily dismissive tone, something like “ah, our members of parliament only care about their careers”, you can demolish the lie for once and for all. They don’t. They care deeply about their wallets, too.

Was Ray Lewis – for a very short period the deputy mayor of London – a reformed child abuser and fraudster? You sort of hope not. It is wholly commendable that the capital’s new mayor, Boris Johnson, wished to run an inclusive and diverse administration – and undoubtedly, in the past, many of London’s vibrant community of child abusers and fraudsters may have felt themselves unrepresented at a high level.

But I’m not sure how this would have played abroad, when we put in bids for high-profile stuff, athletics meetings and so on. Foreigners often take a dim view of cruelty to children and a large minority are not keen on fraud either. Laudable though Johnson’s perhaps surprising commitment to diversity may be, the whole Lewis business might have played against us in the future.

On Friday, the wretched Lewis resigned, having suffered accusations that he had borrowed large sums of money from his parishioners, when he was a Church of England priest, and didn’t pay it back very quickly. Cheques bounced, or were not sent at all, and so on. There were also allegations about him abusing kids at a children’s academy and that he enjoyed dubious sexual relations with a couple of his parishioners, in an ungodly manner. He has denied all these allegations. But he also told people he was a magistrate when he wasn’t. What we know for a fact is that he was suspended from the Church of England, a disciplinary procedure which he later claimed not to have known about at all. Either way, the knives were out for him.

Here was the chance for opponents of Johnson’s mayoral administration to secure their second scalp within two weeks. Johnson’s chief political adviser, James McGrath, was kicked out 12 days ago for having replied rather brusquely to a black journalist who said that some Afro-Caribbean people who were affronted by Boris’s electoral victory might return to their country of origin as a consequence.

“Well, if they want to go, let them go,” McGrath replied – and was promptly sacked for “racism” as a result.

Quite a lot of people were appalled by McGrath’s peremptory removal for having said something which was not, by any stretch of the imagination, racist at all. And now, hearing of Lewis’s resignation, one former member of Johnson’s team told me: “It’s absolutely clear. They’re going to pick us off one by one.”

Yes, that’s right. Not least because they found it so easy to do the first time around – with the case of McGrath – and have scored a bull’s-eye again: if you can manipulate the sacking of someone for having said something with which nobody, save for a tiny minority of perpetually affronted agitators, found offensive – then hell, it’s open day on the entire regime. By the same token, if you sack someone forthat, how can you not sack someone when these rather more serious allegations bubble to the surface?

Lewis hung on for a while, having a few things going in his favour, even beyond the fact that – allegedly fraudulent behaviour and accusations of child abuse notwithstanding – he has reportedly done excellent work within the community. Primarily this: Lewis is himself of Afro-Caribbean descent and so, it seems, the bar was not set quite so high as it was for poor McGrath. And you might wonder, too, if the bar was set quite as high when Lewis was invited by Boris to become the deputy mayor of London. In a press conference Boris said he had no knowledge of his deputy’s suspension by the Church of England.

It is tempting to conclude that Boris impetuously leapt at the chance of appointing Lewis, partly because of their shared values but also partly because of Lewis’s race: quite unfairly, Boris does not have a great reputation among some sections of the immigrant community.

The new mayor of London is in a jam and haemorrhaging senior staff. This is because of the way he was persuaded to treat McGrath, who was guilty of nothing. Racism is a corrosive thing, whatever way you look at it.

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