There has been some debate in recent months concerning a second Scottish Independence Referendum. The key issue in this debate is whether the Scottish Government and Parliament have the competence to hold such a referendum without the devolution of authority by the central United Kingdom (UK) government. If a second referendum is to take place and be effective, it is crucial for the Scottish Government that it be conducted on proper legal footing to ensure it is legally valid.
In June 2022, First Minister Nicola Sturgeon announced plans to hold a second Scottish independence referendum on 19 October 2023. Sturgeon has indicated that she remains open to negotiate formal consent for the vote to be held but would continue with the referendum even if this was not granted. However, Sturgeon has stressed that the referendum would be lawful and constitutional - the UK Supreme Court would have final jurisdiction to decide whether Scotland could hold such a vote unilaterally.
The first independence referendum in 2014 was able to be held due to the Edinburgh Agreement and an Order in Council passed under Section 30 of the Scotland Act 1998 (the 1998 Act) which allowed for a modification to Schedules 4 and 5 of the Act. Schedule 5 of the 1998 Act lists matters reserved to the UK Parliament and Government which includes "the Union of the Kingdoms of Scotland and England" under the broad heading of "The Constitution"; therefore, an Order in Council was needed to allow a referendum to be held in Scotland.
Therefore, if the UK Government does not grant another Order in Council - which currently seems unlikely as the first referendum was described by Alex Salmond in 2014 as a "once in a generation" vote – the question arises: "Does the Scottish Parliament have the power to hold a referendum unilaterally?"
The legislative powers of the Scottish Parliament are set out in the 1998 Act; Section 29 sets out the legislative powers of the Scottish Parliament and states that they cannot legislate on reserved matters. Reserved matters include "the Union" under "The Constitution". This has been taken to confirm that Scotland cannot hold a vote on independence without Westminster’s approval. However, the Scottish Government has brought forward a Referendum Bill and has argued it has the power to hold such a referendum, although it is not entirely clear on what basis the Government thinks it has the lawful power to hold a referendum.
One obvious issue in this debate is Section 29, which states that an Act of the Scottish Parliament is “not law” if any provision is outside the competence of the Scottish Parliament (if it “relates to reserved matters”). Therefore, much will turn on the idea of "relating to"; Section 29(3) states that this is to be determined by the purpose of the provision. It therefore seems, as argued by Stephen Tierney, Professor of Constitutional Theory at the University of Edinburgh, intuitively obvious that a referendum that seeks to end the Union would "relate to" the Union and thus be unlawful. However, Tierney also raises the issue of an "advisory" or "consultative" referendum, in which the purpose and result would not directly end the Union and it may be within competence. Sturgeon herself has argued for this, stating that such a vote “will not in and of itself make Scotland independent”. This argument loses some credibility due to the nature of how the 2014 referendum was conducted; it was accepted by the Scottish Government that it required an Order in Council to transfer temporary competence.
Ultimately, this is a matter of interpretation that the Supreme Court would have to appraise. There have been previous rulings where the court has considered the key question of "relating to" reserved matters (Section 29), such as Martin v Most (2010) and Imperial Tobacco Limited v The Lord Advocate (2012). In these cases, the Supreme Court drew the boundary between devolved and reserved matters. For example, in Martin, the Court concluded that a provision would be outside Scottish competence if it had more than a “loose or consequential connection” to a reserved matter. Therefore, the Court takes a particular approach to the 1998 Act which suggests a tight interpretation of Section 29. Thus, the question is whether a referendum on Scottish independence would have more than such a loose or consequential question to the Union; Tierney rightly argues that it seems probable that the Supreme Court would find such a connection to exist. As McCordindale and McHarg, both Professors of Public Law, state, “there is no legal right to insist upon Scotland’s independence or its competence to hold a referendum”.
There is another case in the Scottish courts that also reinforces this view. In Martin James Keatings (2021) the Court of Session Inner House was asked to pronounce a declarator that the Scottish Parliament would have the power to hold an independence referendum without requiring the consent of the UK Parliament. The Inner House refused to do so, stating that the matter was premature, hypothetical and academic. Interestingly, Lord President Carloway stated that “it may not be too difficult to arrive at a conclusion”; Tierney argues that one plausible reading is that the Parliament does not have competence (as this notion is a generally accepted premise). However, this is an issue that would finally be determined by the Supreme Court and not the Court of Session.
It is likely, in the face of previous rulings and past precedent, that Scotland does not have the competence to unilaterally hold a second independence referendum. However, this is an issue for the Supreme Court to decide and the Lord Advocate has referred the case to the Court, who will hear the case in early October of this year. Much, potentially including the future of the United Kingdom, will hinge on their interpretation and ruling on the issue. If there is no legal route for the Scottish Parliament to hold the referendum, then the respective political actors for Scotland and the UK will need to arrive at some form of political agreement, either for the referendum or to make efforts to restore faith in the Union.