NICOLA Sturgeon is consulting widely on her future tax plans, as she announced last Thursday. It can only be a good thing compared to the secrecy in which these things are done in Whitehall. The Chancellor of the Exchequer traditionally goes into what his mandarins call purdah before the annual Budget – not that this leads to better decisions.

But despite the openness of the Scottish process, one particular sort of fiscal programme – much more coherent and much more successful than most that are at present operating worldwide – seems unaccountably to have been left off the First Minister’s possible agenda. What I mean is a programme of freezing taxes or even cutting them – though admittedly in Scotland the second option must remain some way off, given the size of our budget deficit.

Before all my Marxist friends and admirers throw up their hands in horror and say here is Fry being a capitalist beast again, let me remind them that already one of the most successful gambits of the SNP government since it came to power in 2007 has been to freeze an important tax, and most effectively too. What I mean is the freeze on council tax, which accounts for four per cent of all revenue raised in Scotland but for 19 per cent of local government’s revenue, so at that level it is important. The freeze has only just been lifted again, giving us the rare and valuable opportunity of assessing the practical operation of a particular tax policy over a whole decade, without interruption or distraction. Some of Whitehall’s bright ideas have lasted three weeks.

Even if the freeze was originally framed just as a crowd-pleaser, for the populist purpose of hoovering up electoral support, it produced results which could hardly have been dreamed of at the start. It obviously did nothing to put the voters off because, over those 10 years, they steadily swung to the SNP, regardless of the howls from the other parties about damage to services. Today those parties have only begun to gain ground again now that the freeze is over. In between there were some tough times, and householders will have been happy that at least one item of their unavoidable expenditure was not going to go up. I would say a lesson from this episode is: if you want to win votes, freeze taxes.

Of course, the freeze never turned into a squeeze. Labour claimed that “heavily centralised commitments, such as the underfunded council tax freeze, are placing an unbearable burden on local authorities”. The local authorities themselves don’t seem to have thought so, or at least they seldom said so. In fact on a longer-term view, from the start of devolution in 1999 up to the latest financial year 2015-16, their share of public spending has remained steady. Central government, seeing that during the freeze many might have found a gap opening up between revenue and expenditure, contributed £70 million a year to their budgets. In the event, this inflow exceeded what they would have got if, over the same period, council tax has risen by the rate of inflation. Revaluations also helped, because they defied the freeze.

Still we can conclude that, from the Scottish Government’s point of view, the freeze proved to be a brilliant success, and I would say from the voters’ point of view too. The multiplication of potholes in the roads was the only snag I can think of, and this we may owe just as much to many councils’ hostility to motorists and their refusal to spend on what motorists need. Otherwise the councils presumably coped by becoming more cost-conscious and efficient, by postponing capital expenditure and by cutting down on personnel. Of course the consequent strains had at last to be relieved by an end to the freeze. But its 10 years were good for us. After a period of adjustment to new calls on public money, I hope that before long we can try out a freeze once again. It may even be the thing to save the Scottish Government from the doldrums into which it has meanwhile sunk.

Or else, given the obvious correlation between fiscal restraint and success for the SNP, perhaps it is time to try a freeze on a different tax. How about a freeze on the Scottish income tax for 10 years ahead? This at the very least is a simple measure, compared to the weird and wonderful complications included in the First Minister’s range of proposals. It would leave more money in people’s pockets. That would encourage consumers’ expenditure, which in Scotland has been limping along behind the level in the UK. This in turn would do most to raise the woeful growth rate in the Scottish economy as a whole. And it would also offer scope for an increase in savings and investment, our most urgent need of all, without which post-oil Scotland will steadily sink to be once again among the economic sick men of Europe.

I do not think this freeze on spending would necessarily leave the Scottish Government short of real resources. Thanks to Brexit and the slump in sterling we are now, after a long period of fairly stable prices, moving into an era of inflation once again: it is already running at three per cent and not coming down any time soon. What is more, Nicola Sturgeon has herself lifted the cap on public-sector pay and, to go by past experience, the private sector will soon catch up. But all this is good for the revenue. The yield from taxes will rise and more people will move on to the higher rates. That will mitigate some of the obviously negative effects of a freeze on taxes.

But if we are going to freeze taxes, then we should really freeze public expenditure as well. The freeze need not be absolute. We should exempt spending for investment, items like the Queensferry Crossing, the Aberdeen bypass or the research hub for Glasgow University. These will all help us to raise our national income in the future and meanwhile, till the borrowing is repaid, only cost the taxpayer the interest on it. We also have to exempt expenditure which is demand-driven, such as unemployment benefit, though much of this money is non-devolved and not under the direct control of the Scottish Government anyway, so not a problem for us. But that means we need to be all the stricter about inessential current expenditure in Scotland, baby boxes for example: very nice in a coochy-coo kind of way, yet hardly necessary for national survival in hard times.

And national survival is what in the end we are talking about here. To give a contrary example, one reason Germany is going to stay top nation in Europe is that it always balances its budget, and even after the greatest crises returns as quickly as possible to balance, by tax rises or spending cuts. It can then choose whatever investments it likes, because the money is always there. Compare that to Scotland, forever struggling to find resources for investments and after decades of Unionist mismanagement from London suffering a huge backlog of projects which it would be good to do but which can’t be afforded.

This will remain so after independence. Our unstoppable urge for expenditure will then sooner or later run up against the conditions set by the international financial markets, from which by that time the money will need to be borrowed. More likely before this happens, the EU, as we seek to re-enter it, will demand from us commitments to the Maastricht criteria, under which we would be required eventually to adopt the euro. That would limit our budget deficit to three per cent of gross domestic product, in other words cut it by at least a half, probably more, from what it is now. Does all this sound like a tall order for happily spendthrift, egalitarian Scotland? Well, it is. That is why I say once more that, without a fresher approach to fiscal policy than we saw last week, Scotland will never become an independent country.