The Supreme Court on Devolution

What role does the Supreme Court play in devolution?

The Supreme Court is the United Kingdom’s final court of appeal for civil cases, which combined with the Court’s devolution jurisdiction, secures the Court a significant role in shaping the development of the law on devolution.

Since the establishment of the Court in 2009, there have been a number of significant judgments on devolution, in particular as a result of references made to the Court from the National Assembly for Wales.

These judgments contain analysis, in the form of the interpretation of the devolution statutes, which informs the constitutional and legal meaning of the UK’s devolution settlements.

What powers does the Supreme Court have in relation to legislation made by the devolved legislatures?

Each of the Scotland Act 1998, the Northern Ireland Act 1998 and the Government of Wales Act 2006 enables the Supreme Court to rule that primary legislation, made by each of the devolved legislatures, is outside of competence. Each of the devolved legislature’s legal power, its legislative competence, is defined by the relevant devolution statute.

The Supreme Court must decide, when it is contested, whether a particular provision is within the legal powers granted to the devolved legislature by Parliament in the corresponding devolution statute.

How do devolution cases reach the Supreme Court?

There are broadly three routes. The first is through a reference of a Bill that is before a devolved legislature by one of the law officers.

The second is through a statutory reference or appeal of a "devolution issue" to the Court. The devolution statutes provide for a special procedure for “devolution issues” raised in litigation, including the legal validity of an Act made by the devolved legislatures, to be referred or appealed from certain courts to the Supreme Court.

The third is through the normal judicial process, with cases arriving at the Court on appeal from lower courts.

Which Supreme Court cases on devolution have been particularly significant?

The Supreme Court case of Agricultural Sector (Wales) Bill in 2014 had a major impact on devolution in Wales. The UK Government had challenged the legality of a National Assembly for Wales Bill on the basis that Bill went beyond the powers specified in the Government of Wales Act 2006.

The Supreme Court ruled that the Bill was within the Assembly's legislative competence because the Assembly could in certain circumstances legislate for subjects which were not specified as exemptions under the Government of Wales Act 2006.

In the case of Salvesen v Riddell in 2013, the Supreme Court held that a provision in the Agricultural Holdings (Scotland) Act 2003 was incompatible with the right to property as set out in Article 1 of Protocol 1 of the European Convention of Human Rights.

The Scottish Parliament cannot, according to section 29 (2) (d) of the Scotland Act 1998, legislate contrary to Convention rights. The human rights dimension to the restrictions on the powers of the Scottish Parliament has proved especially significant, and has given rise to a number of the challenges to Acts of the Scottish Parliament that have reached the Supreme Court, including The Christian Institute and others v the Lord Advocate [2016].

What does this briefing cover?

This briefing paper provides an analysis of a selection of the most important judgments of the Supreme Court on devolution to date. The first section sets out the basic constitutional context. The second section outlines how devolution cases reach the Supreme Court. The third section examines some of the devolution cases decided by the Privy Council and the House of Lords prior to the creation of the Supreme Court in 2009. The fourth section covers the Supreme Court’s most notable devolution cases in chronological order.