In July 2019, the Scottish Parliament will celebrate the 20th anniversary of assuming its first tranche of devolved powers. Those came to life when relevant provisions of the Scotland Act 1998 were commenced and then significantly supplemented by the Scotland Acts of 2012 and 2016. 

Now we have to face the issue of what the UK's withdrawal from the European Union, or Brexit, will mean for the powers of the Scottish Parliament and Government.

That issue has to be seen in light of provisions of the European Union Withdrawal Act 2018, which received Royal Assent in June, and how certain powers granted by that legislation will be implemented. For instance, under the Scotland Act it is currently outside the legislative competence of the Scottish Parliament to do anything that is incompatible with EU law. 

In the post-Brexit world that restriction is to be removed, only to be replaced by a provision which states that an Act of the Scottish Parliament cannot modify "retained EU law" so far as the modification is of a description stated in regulations made by a Minister of the Crown. Broadly stated, the reference to "retained EU law" is to the body of law in the UK derived from various EU sources since 1973, which will be preserved with a new legal base on Brexit under the 2018 Act. 

The 2018 Act also provides that the new restriction is not to apply to any modification of the law that was within the competence of the Scottish Parliament immediately before withdrawal from the EU.

These new provisions, which are not the simplest to navigate, recognise that functions of EU institutions will be repatriated on Brexit, and that some of these might fall within devolved legislative competence. But, just as the Act of Union of 1707 recognised that certain areas of law should be the same throughout the new common market of the then nascent United Kingdom, so here the UK Government will have the power to specify those areas where it envisages common frameworks of law being maintained across the UK post-Brexit. These will be specified areas of retained EU law over which the Scottish Parliament will not have legislative competence.

It follows that in devolved areas of law, where there has been no such specification, repatriated EU functions and related law will be subject to modification by the Scottish Parliament. In that way, the powers of the Scottish Parliament may increase following Brexit.

Under the 2018 Act, where a UK Minister proposes to specify areas of retained EU law whose modification is to be outside the legislative competence of the Scottish Parliament, a procedure is set out for doing so. This includes notifying Scottish Ministers and the Scottish Parliament of the Minister's draft regulations, before they are laid before both Houses of the UK Parliament for approval. The Scottish Parliament can consent to the regulations being so laid, but, even if it does not, the Minister ultimately can proceed as the Scottish Parliament has no veto over this matter.

There are "sunset" provisions relating to these regulation-making powers. First, no regulations of this kind may be made after a period of two years from the date of Brexit. Second, restrictions on the legislative competence of the Scottish Parliament contained in such regulations, if they have been in force for five years, will not apply to legislation enacted after that five year period. Provision is also made to enable a Minister of the Crown to repeal these regulation-making powers, taking account of the fact that the powers, and any restrictions arising under them, are intended to be temporary and may be replaced by other arrangements.

To say that there has been political dispute between the UK and Scottish Governments over the above provisions might be an understatement. The political debate has, however, raised interesting constitutional issues that are well beyond the scope of this short note. One can but await the outcome of political action and witness the way in which the powers under the 2018 Act are exercised. Only then will there be a clear picture of what new powers the Scottish Parliament has at the time of the UK's withdrawal from the EU, but also in what ways its legislative competence is restricted.

Article author: Charles Mullin. Charles, formerly of Shepherd and Wedderburn, is Convener of the Constitutional Law and Human Rights Sub-Committee at the Law Society of Scotland

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