The Scottish Parliament’s original powers were set out in the 1998 Scotland Act. Rather than explicitly granting powers to MSPs, the law outlined which areas were to be ‘reserved’ to Westminster leaving Holyrood free to legislate about everything else.

At the outset, that meant education, agriculture, housing, the environment and health and social care were in the new parliament’s purview. Justice, economic development, arts culture and sport too. Although successive administrations have chosen not to use them, voters had also decided that the new Scottish Executive would have tax-raising powers - able to raise or lower the basic rate of income tax by up to three pence in the pound.

The 2012 Scotland Act varied this, allowing the parliament to vote to raise or lower income tax by up to 10 pence in the pound, so long as any change affected all tax bands. The Scottish Government, as it had been known since 2007, was also given the power to borrow up to £5 billion.

A third Scotland Act, in 2016, expanded the Scottish Government’s powers further, including the power to alter Air Passenger Duty in Scotland – the SNP have just U-turned over plans to use it. Similarly timely is the power the act granted to amend a Holyrood electoral system described as “unloved and overly complex” in the Herald yesterday by leading civil servant Sir Michael Grice.

A major change was the extension of control over eight benefits - including the housing element of Universal Credit, carers allowance, disability assistance and the ability to top up reserved benefits. This has led to the establishment of a new agency, Social Security Scotland - based in Dundee - which ministers promise will usher in a new respect-based approach .

But this steady growth in the Scottish Parliament’s powers is contrasted with the UK Government’s alleged ‘land grab’ in areas of law which will be ‘repatriated’ after Brexit, such as agriculture, fishing and food standards. This is likely to remain an area of tension.