IT is not always the case that Parliament can assert itself without even meeting – never mind voting – but the new Chancellor Kwasi Kwarteng U-turned on his short-lived policy to abolish the 45 per cent additional rate of income tax for one reason, and for one reason only. He would not have got it through Parliament.

British politics is always at its best when Parliament asserts itself. Ministers like to think they control Parliament – and so they do, all too often. But Parliament, in the end, holds the whip hand. It is Parliament that can unseat a Prime Minister (as Mr Johnson discovered to his cost this summer). It was Parliament that ensured we never left the European Union without a deal. And it is Parliament that can make or break a Budget, even an apparently mini one.

It is the same in Holyrood. No Scottish minister can get a budget through without parliamentary support and, in the Scottish Parliament (where no one party enjoys an overall majority), that means cross-party support. Now, views will differ as to just how cheaply the Greens have sold their votes when it comes to supporting SNP budget proposals over the years. But let’s leave that to one side. For the fact is that, whether it be John Swinney or Kate Forbes, no Scottish finance secretary could have done in Holyrood what Mr Kwarteng did in the House of Commons less than a fortnight ago.

That is to say, no Scottish finance secretary could simply rock up, announce breathtakingly broad fiscal measures with no background checks having been carried out on them, seek to impose budgetary measures supported by only a minority of MPs, and act as if it was all a done deal, only to watch, aghast, as first the markets and then the politicians started taking bite-sized chunks out of them.

Until last year’s SNP/Green pact, which has short-circuited the power Holyrood would otherwise have had, rendering much of its work pointless, budget announcements in the Scottish Parliament were statements of policy intent – what the Government would like to achieve, if it could find cross-party consent – not announcements of done deals.

Parliamentary poodle

Mr Kwarteng, by contrast, acted as if Parliament were his poodle and would do his bidding no matter what. Perhaps such hubris is understandable if you have just returned from the country with a freshly elected 80-seat majority. But it is foolish to the point of embarrassing if all you’ve done is return from having been appointed by a new Prime Minister whom most of your own MPs did not even want. Will the Truss administration learn from this debacle? Will they absorb the lesson that it is they who are accountable to Parliament’s judgment, and not the other way around? We shall see. Personally, I’m not holding my breath.

More importantly, will Sir Keir Starmer learn from it? He has been in the House of Commons for long enough now to have witnessed it at its potent best and at its craven worst. When, next year, he becomes only Labour’s third Prime Minister since the Second World War to win a General Election (as he surely will), what will he want from Parliament? Will he want a reformed chamber, to which no Chancellor could come in anything but supplication? Or will he repeat the self-serving mistakes of so-called progressive governments of the past, and do as if Parliament is there to serve him?

For there is one change – one change above all others – that could finally transform British politics overwhelmingly for the better. Tony Blair and Gordon Brown resisted it when they were in office, for they turned out to be as backward in their thinking about parliamentary accountability as Mr Kwarteng and Liz Truss are. Sir Keir should learn not only from his own recent observations but from his party’s long history of missed opportunities. Sir Keir’s Labour should finally bite the bullet, and revolutionise the House of Commons.

The means of doing so are readily at hand. All we need is electoral reform. I don’t mean the half-way house of the additional member system we have in Holyrood. Admittedly, that’s better than the current first-past-the-post system under which the Commons still suffers, but a fully proportional system is what British politics so desperately needs.

Electoral reform

British politics needs proportional representation – PR – because it is the only way of ensuring that governments act genuinely in the interests of majorities rather than in response to the echo chambers of their own partisan supporters.

British politics needs PR because a House of Commons in which no one party has an overall majority will produce responsive, pragmatic, intelligent government, rather than the ideological mania we have right now.

And British politics needs PR because it will lead directly to a realignment of our unfit-for-purpose political parties. It is obvious that both the UK’s major parties are unhappy coalitions. The hard-left Corbynistas no more belong in a reformed and electable Labour party than the centre-right moderates belong any longer in what the Tory party has become – a crusade of Brexiteer Trussomaniacs.

Yet they cleave miserably together because the electoral system demands it. Change the electoral system and you change politics. It’s the one big constitutional reform Britain needs.

We know that the Labour Party – north and south of the Border – is considering various aspects of constitutional renewal. Reform of the House of Lords. Further devolution. Decentralisation. A rebooting of local government. The party can navel-gaze about all that as long as it likes – none of it will matter much if the House of Commons, the centrepiece of British government, goes untouched.

Sir Keir Starmer has a big choice to make: does he want to be a pale imitation of Blair and Brown; or does he want to be the man finally to break the mould of British politics, unleash Parliament, and ensure that never again are we subjected to a regime that governs not for the public at large, but for its own small band of swivel-eyed true believers?

Adam Tomkins was a Conservative MSP for the Glasgow region from 2016 to 2021.

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