The National:

THE United Kingdom Internal Market Act 2020 is the third Westminster statute to be passed since 2018 in the face of an explicit refusal of consent (under the Sewel Convention) by one or more of the devolved legislatures. The Act establishes a new legal framework to minimise the impact on trade within the UK arising from potential regulatory divergence between Scotland, England, Wales and Northern Ireland after the Brexit transition period ends.

The House of Lords Constitution Committee described the Bill as “one of profound constitutional significance” for the UK’s devolution arrangements, and regretted the lack of engagement with the devolved governments in developing the proposals. Both the Scottish Parliament and the Senedd (Welsh Parliament) voted to refuse consent to the Bill, and although no formal legislative consent motion was lodged in the Northern Ireland Assembly, in September the Assembly also approved an SDLP motion to reject it.

The Bill was heavily amended by the House of Lords and – remarkably – peers maintained their objections through three rounds of “ping pong”. However, that came to an end this week, when peers dropped their opposition to provisions allowing UK Ministers to spend in devolved areas (many of them nothing obviously to do with trade), to the reservation of power to set state aid (subsidy) controls to Westminster, and to the very narrow exceptions in the Bill from the operation of the internal market principles. In turn, the UK Government conceded amendments to clarify the relationship between those principles and so-called “common frameworks” (for instance, on food safety rules) agreed between the UK and devolved governments. These came on top of earlier concessions committing to consultation with the devolved governments over future changes to the scope of the internal market rules.

READ MORE: UK goes ahead with Internal Market Bill without consent from Wales or Scotland

While these amendments are welcome, they do not fundamentally alter the impact of the legislation on the ability of the devolved institutions to legislate in distinctive ways for their territories in future. While the devolved legislatures will, at the end of the Brexit implementation period, gain new powers in areas previously dealt with at EU level, their ability to make use of these powers will be severely constrained, particularly if they wish to adopt policies which are different to those which apply in England. Although the practical impact of the Act is hard to predict, it undoubtedly makes a fundamental change in principle to devolved legislative competence, limiting the scope of future devolved regulations to traders or service providers based in Scotland, Wales or Northern Ireland, rather than to anyone trading in those markets. It also significantly extends the powers of UK Ministers to influence decision-making in devolved areas via their new spending powers.

The amendments to the Bill were not, therefore, sufficient to enable the Scottish and Welsh Governments to recommend that consent be given. But the Bill was granted Royal Assent anyway, with the UK Government claiming that this is one of the exceptional circumstances in which the Sewel Convention permits Westminster to proceed without devolved consent. The Welsh Government has now stated its intention to begin legal proceedings, seeking a declaration that the new Act must not be read as undercutting devolved competence. The devolution statutes, as constitutional statutes, may only be amended expressly and not by implication, and the Welsh Government argues that the UK Internal Market Act does not make its effect on devolved competence sufficiently clear.

Such legal action is unprecedented, and its chances of success seem slim. But the turn to the courts is symbolic of a profound loss of faith in the ability of political constraints, such as the Sewel Convention, to protect devolved autonomy against the “muscular” – and centralising – Unionism that has been unleashed by Brexit.

READ MORE: SNP MP Drew Hendry on the Internal Market Bill and his Commons suspension

The UK Government maintains that it is still committed to the Sewel Convention – and indeed the consent process does appear to be operating normally outwith the context of Brexit-related legislation. Nevertheless, a constitutional rule which contains an undefined exception, which can be invoked at will by one party to disputes over its application with no prospect of any appeal to an independent adjudicator, scarcely deserves to be described as a rule at all.

Aileen McHarg is a professor of public law and human rights at the University of Durha. The National will be donating the fee for this article to Crisis at Professor McHarg's request