Rates of change: Holyrood and income tax

MSPs are set to sign off on changes to the income tax system which will affect more or less every taxpayer in Scotland. How did we get here, and what might happen next?

In the devolution referendum of 1997, Scots voted not just to have their own parliament, but to have a parliament with tax-varying powers.

Now, some 20 years later, Holyrood is poised to take a significant step away from the UK's income tax system.

The change has arguably been a long time coming. For the first four terms of the Scottish Parliament, no significant moves were made to reform the tax system - chiefly due to a lack of powers.

MSPs were initially given the option of a Scottish Variable Rate of income tax, which would have let them shunt rates up or down to the value of 3p in the pound.

This option was never used, either by the Labour-Lib Dem coalition which initially ran Holyrood, or by Alex Salmond's SNP administration - which routinely did budget deals with the Conservatives during its years as a minority government, not generally a recipe for radical fiscal experimentation.

The SVR deal was allowed to lapse in 2007, and was actually taken away for a period - not that this bothered Scottish ministers, with the then Finance Secretary John Swinney dismissing it as "unusable and expensive".

Even after amassing an unprecedented Holyrood majority in the 2011 elections, Mr Salmond's government made little effort to alter the tax system - with an independence referendum in the offing, they were were more interested in making constitutional changes. Why reform devolved taxes today when you might have independent ones tomorrow?

While that referendum failed to trigger the constitutional change Mr Salmond had hoped for, it did usher in a wave of new powers which have seen more and more variance from UK systems in recent years.

The first raft of powers came via the 2012 Scotland Act, which gave ministers their own versions of landfill tax and stamp duty to play with in 2015. This established a base of change, but didn't make a huge difference in most people's lives.

These first steps were followed by a Scottish Rate of Income Tax in 2016. Put simply, this took 10p in the pound off the three existing tax bands (with a corresponding reduction in Holyrood's block grant) and allowed Scottish ministers to set a rate to replace this.

This was a bit of a blunt instrument compared to the fiscal scalpel wielded today, allowing only a block change to all bands - basic, higher and additional. So there would be no way of taking exclusively from the rich and giving to the poor; everyone would see their taxes rise or fall together, in percentage terms.

Ultimately Mr Swinney chose not to make any changes for 2016-17, setting the SRIT at 10p - mirroring the status quo situation. He argued that raising taxes across the board - as Labour and the Lib Dems wanted to do - would punish working people. There was also a Holyrood election on the horizon to think of.

Mr Swinney also argued that the government would be able to take a more "progressive" approach once Scottish ministers had the ability to set rates and bands - something which became official, under another Scotland Act, later in 2016.

It was with these extra powers in hand that Mr Swinney's replacement as finance secretary, Derek Mackay, made the first proper break with UK policy in the 2017-18 budget.

It wasn't a big break, in many ways - merely to freeze the threshold of earnings where the higher rate kicks in, a change which the majority of taxpayers in Scotland wouldn't even notice. The rates and bands themselves remained the same - Mr Mackay was basically just not passing on a tax cut for the better-off planned at Westminster.

The threshold freeze did raise a bit of extra money - including £107m to finance a budget deal with the Greens - but the cash was a drop in the fiscal ocean when set against Holyrood's budget as a whole.

It did, however, open the door to greater changes in future - and drew a distinction with the rest of the UK, where some higher earners were now being taxed less than people on the exact same wage north of the border.

The tax changes for the 2018-19 budget are far more noticeable than those agreed for the previous year.

Mr Mackay's latest proposals will impact on just about every taxpayer in Scotland - many of whom will actually end up paying less.

The redistributive plan doesn't entirely tear up the existing, UK-inspired system - there is still a 20p basic rate, and the higher and additional rates live on with a penny added to each. But there are significant additions, in the form of a 19p "starter" rate for lower earners, and a 21p "intermediate" rate to help pay for it.

The starter rate, taken in combination with the increase in the tax-free allowance instituted from Westminster, means 70% of Scots will actually pay less income tax than they did the previous year.

While this is undoubtedly good news for that 70%, the sums involved are not vast. The Scottish government's own figures say those on £15,000 per annum will benefit to the tune of about £90 in the coming year - while those on £50,000 will stump up a grand total of £84 more than they did in the previous year.

Basically, we're talking about no more than a couple of quid a week, for the majority of Scots. Any extra money will be welcomed, but nobody is going to be rushing out to buy a speedboat with the money they're saving on tax - nor will anyone at the other end of the spectrum be forced to sell theirs.

There are bigger changes in the comparison to taxpayers elsewhere in the UK, but again they are not huge, for the majority of taxpayers - the £15,000 workers of Gretna will be £20 a year better off than their neighbours in Carlisle, and those on £33,000 will be £70 worse off. The numbers are bigger for those on six-figure salaries, but still in the area of about a penny in the pound.

Overall, the changes are going to raise roughly £420m - which is technically a lot of money, which could do a lot of good for local services. But it's really a drop in the ocean when you consider the overall Scottish budget is in the region of £32bn.

But the SNP can argue that they are pursuing a more progressive approach, cutting bills for lower earners while asking the better-off to pay more - and raising some cash to protect local services in the meantime.

The changes made with Holyrood's tax powers so far have not raised eye-wateringly huge amounts of money, when looked at on the scale of a multi-billion pound budget. But these first steps have opened the door to potentially radical changes in the future.

Scotland is now moving in a different direction to the rest of the UK when it comes to tax. Only the Scottish Conservatives have argued against this movement, with other opposition parties calling for even greater changes.

In the current parliament, a SNP-Tory deal of the sort Mr Salmond used to secure looks vanishingly unlikely - so any party the SNP ultimately do partner up with to pass a budget are likely to be pressing for more and more use of tax powers.

Labour has proposed "radical" bands and rates which they claim would push the amount raised into the billions, rather than the present hundreds of millions - although their methodology has come in for quite a bit of criticism from Mr Mackay.

The Greens, keen not to be seen as a cheap date for the SNP, have already started banging the drum for further changes next year, with the intention of giving local authorities a better deal.

For all that they have now backed consecutive SNP budgets, the Greens actually have an even more radical position on taxation than Labour, having campaigned on a 60p top rate of tax in the 2016 elections.

The Lib Dems are always in the room for budget talks too, and have been pressing for extra cash for education and mental health, and have campaigned for a "penny on income tax" across the board to fund this.

There are also other taxes in the mixer - like Air Passenger Duty, the devolution of which has somewhat stalled over technical matters. This is actually good news for Mr Mackay when it comes to dealing with the Greens, who dislike his aim of cutting the levy in the long run, but is not a situation which will continue indefinitely.

And what of future parliaments? With the precedent now set for Scotland to go its own way in terms of taxation, would a future Holyrood administration of any colour feel the need to move back into lockstep with Westminster?

While the figures involved in today's changes may not be vast, these are moves which could have far-reaching consequences way off into the future.