NICOLA Sturgeon last week kickstarted the new independence campaign. This will be a political campaign which will be fought in the media, online and on the streets for the hearts and minds of the Scottish people.

But there will be a second campaign, a legal one, which will be fought largely between lawyers and legal academics for the minds of the judiciary. This will be over the question of whether an independence referendum is lawful under the Scotland Act 1998.

The legality question matters because only a lawful referendum will command legitimacy needed to secure Scottish independence and for that reason the First Minister has consistently argued for a lawful referendum.

An excellent summary of where the legal debate is can be found in the new House of Common research paper by David Torrance available at researchbriefings.files.parliament.uk/documents/CBP-9104/CBP-9104.pdf

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In the independence movement there is much talk of the sovereignty of the Scots people. While as a citizen I entirely support the principle of the political sovereignty of the Scottish people, as a lawyer

I regret to say matters are not so clear-cut in law.

The basic problem is that in law it is the Westminster Parliament that is sovereign not the Scottish people. The Scottish Parliament is a creation of Westminster via the Scotland Act.

The Scotland Act “reserves” certain areas to Westminster and in reserved areas Holyrood has no ability to make law. So the legal question is: “Can Holyrood lawfully authorise a referendum on Scots independence without the consent of Westminster?”

If Holyrood passes a bill authorising indyref2 that will certainly be challenged in court either directly by the British government or by a Unionist litigant with deep pockets (of whom there are many). So the issue will certainly go to court.

The boundaries of the competence of the Scottish Parliament are set out in ss. 28, 29 and schedule 5 of the Scotland Act. Section 29 of the Act sets out the “legislative competence” of Holyrood in a way which excludes “reserved matters” one of which under schedule 5 is “the Union of the Kingdoms of Scotland and England”. The legal task of the courts will be to interpret the words of the Scotland Act, no more but also no less.

The key words are found in section 29 on legislative competence: (1) An Act of the Scottish Parliament is not law so far as any provision of the Act is outside the legislative competence of the Parliament.

(2) A provision is outside that competence so far as any of the following paragraphs apply …

(b) it relates to reserved matters, so the legal issue is whether a referendum with the question “Should Scotland be an independent country?” is a matter “related to

the Union of the Kingdoms of Scotland and England”? The difficulty is that “related to” is so vague no definitive answer can be given in advance, one can argue it either way.

Unfortunately, however, the tenor of opinion in recent constitutional cases from both the Supreme Court and Court of Session seem to me to indicate that they are both likely to rule that a referendum on that question is outwith the powers of Holyrood and so is unlawful.

IF that happened, it would be very difficult to hold a referendum as the Unionist-controlled local authorities would refuse to organise it and anyway the Unionist parties would probably encourage their supporters to boycott any such wildcat election, thus undermining the very democratic legitimacy that independence needs.

So what’s my solution? My suggestion is asking a slightly different question in a referendum. I suggest that the indyref bill should contain authority for two separate bills. The first would be a straightforward independence referendum asking “Should Scotland be an independent country?”

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As explained above a referendum question worded like that will almost certainly be struck down by the courts. However, if there was authorisation for a different referendum bill, one merely requesting permission to hold indyref2 from Westminster, then I believe that might be more likely to be ruled lawful by the courts. Such a referendum could ask: “Should the British Parliament grant legal permission to the Scottish Parliament to hold a referendum on Scottish independence? Yes or No?”

A referendum in these terms is in law (but not politics) merely a grand petition to Westminster and so should be found lawful by the courts under the Scotland Act.

All citizens have the right to petition Parliament! If this petitionary referendum was legally authorised and held and subsequently a Yes vote achieved, then I believe it would then become politically impossible for Westminster to deny Scotland a second referendum.

Because in effect instead of rejecting a Section 30 request from the Scottish Parliament they would be rejecting a request from the Scottish people.

Scott Crichton Styles is a lecturer in law at the University of Aberdeen