NICOLA Sturgeon is to introduce her own legislation to stop a Westminster “power grab” after Brexit in what is shaping up to be most important constitutional clash since devolution.

The Scottish Government will announce this afternoon that it is bringing forward a Continuity Bill to transfer devolved areas of EU law into Scots law once the UK leaves the EU.

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The First Minister is ready to introduce the Bill even if Holyrood’s Presiding Officer, Ken Macintosh, rules it is outwith the parliament’s competence.

The move is also intended to ramp up pressure on the UK Government and force it to rewrite the EU (Withdrawal) Bill to ensure all devolved laws are repatriated to Holyrood at Brexit.

The UK wants around 25 of the 111 devolved competencies to go to Westminster - despite the devolution settlement stating they should be devolved by default - in order to create UK-wide common frameworks protecting the UK single market.

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Essentially the Continuity Bill would be a Scotland-only version of the EU Withdrawal Bill currently going through Westminster, and is designed to maintain EU laws after the UK leaves the bloc.

The Bill will also give Scottish Ministers the power to amend transferred EU law after Brexit.

However it is a controversial measure, which is not guaranteed to succeed. Legal experts warn it could be challenged by the UK government in the Supreme Court.

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The UK parliament could also ignore it and pass its own legislation regardless. However, both actions would be heavy handed, potentially prompting a backlash by Scots and increase support for independence.

It is understood the Scottish Government will withdraw the Continuity Bill if the UK Government changes the Westminster legislation to its satisfaction.

A briefing on the Bill was leaked at Holyrood ahead of a ministerial statement due to take place at 4.15pm.

To succeed, the Bill must pass through Holyrood before it is pre-empted by the EU (Withdrawal) Bill. Under a proposed emergency timetable it will be published by 5pm today, with a further ministerial statement tomorrow and a debate and vote on its timetable on Thursday.

The Scottish Parliament would then aim to pass the Bill by March 21, a day before the UK Government's deadline to amend its own legislation.

Here's the briefing in full:

What is the Continuity Bill?

It is a Bill which prepares Scotland’s devolved laws for the UK’s withdrawal from the European Union. This means that EU laws currently in force will be retained after withdrawal, and the Scottish Government will be given the tools needed to make sure these laws keep working after withdrawal.

It is a devolved version of the UK Government’s EU (Withdrawal) Bill, formally known as ‘the Great Repeal Bill’.

Why is the Scottish Government introducing the Continuity Bill?

The UK Government’s proposed way of preparing for withdrawal is the EU (Withdrawal) Bill, but as it acknowledges, this needs the consent of the Scottish Parliament if it is to become law.

Neither the Scottish Government, the Welsh Government nor (on a unanimous, all-party basis) the Scottish Parliament’s Finance and Constitution Committee currently believe that consent should be given, because of the Bill’s approach to devolution. The Finance and Constitution Committee called it “incompatible with the devolution settlement in Scotland”.

The Scottish Government has always recognised that it need to prepare Scottish laws for the UK’s withdrawal from the European Union. Given the position on consent for the EU (Withdrawal) Bill, a responsible government needs to prepare an alternative, such as the Continuity Bill, as a back-up.

The Scottish Government has delayed introducing that alternative for as long as possible but unless it is introduced in the coming week , under an emergency procedure, it cannot receive Royal assent before the UK Bill does, which would render it pointless. The same situation affects the Welsh continuity bill which will also be introduced this week.

A timeline showing the respective Parliamentary timelines for the UK Bill, the Scottish Bill and the Welsh Bill is provided with this briefing note.

Has the Scottish Government rejected the EU (Withdrawal) Bill?

No. The Scottish Government’s preference is to be able to rely on the EU (Withdrawal) Bill. The Scottish and Welsh Governments continue to seek an agreement with the UK Government, which would allow the necessary consent to be given. In this scenario, the Scottish Government would seek to withdraw the Continuity Bill or would not activate its provisions. The Bill has been drafted to allow that to happen .

How is the Continuity Bill different from the EU (Withdrawal) Bill?

The main difference is that the Continuity Bill gives the Scottish Parliament its full role in the preparation of Scotland’s devolved laws for EU withdrawal. It also gives the Scottish Parliament an enhanced role in scrutinising proposals for changes to laws as a result of withdrawal and makes some different policy choices, including retaining in law the EU Charter of Fundamental Rights. It also contains a power to continue to keep pace with EU law, where appropriate, after the UK leaves the EU.

Is the Continuity Bill within the powers of the Scottish Parliament?

The Scottish Ministers are satisfied that the Continuity Bill is within the legislative competence of the Scottish Parliament. The Lord Advocate has confirmed that position as he is required to do before a bill is sent to the Presiding Officer. We also understand that the Welsh Presiding Officer has signed off the Welsh Bill as competent. However, we do not have confirmation that the Presiding Officer of the Scottish Parliament will also do so. That issue will be resolved today.

In the event of him deciding against giving the Bill a certificate the law and our standing orders still allow the bill to be introduced.

Accordingly , given the positive view of competence of the Bill from the Lord Advocate and a confirming view by the Welsh Assembly Presiding Officer regarding a very similar bill in Wales we are likely to bring the bill to Parliament even if there is no certificate from the Presiding Officer. In those circumstances the Lord Advocate is entitled to, and will, give his reasons for believing it is within legislative competence and would also be happy to meet political parties to confirm that position.

What does the Continuity Bill do?

1. The Bill seeks to ensure that, to the greatest extent possible, continuity of law is maintained on UK withdrawal from the EU. This is to ensure certainty, stability and predictability for the people who live and work in Scotland and those who do business here and with us in Europe. To achieve this, the Bill: · it retains in domestic law EU law currently operating in devolved areas, · it gives Scottish Ministers the powers needed to ensure that devolved law continues to operate effectively after UK withdrawal 2. The Bill is in 6 parts, with the main operative provisions in Parts 2 to 5.

3. Part 2 provides for the retention of existing EU law, whatever its source, so that as far as possible the same laws, rules and schemes will operate after UK withdrawal as they did before. This includes the incorporation of general principles of EU law and the Charter of Fundamental Rights into domestic law.

4. Part 3 sets out the main powers in connection with UK withdrawal. A proportion of devolved law in Scotland contains provisions which will not operate effectively when the UK leaves the EU. Part 3 gives Scottish Ministers powers to correct deficiencies in laws caused by UK withdrawal and sets out the level of scrutiny required to limit the use of the delegated powers.

5. Part 4 sets out the limits and restrictions for setting up and modifying pre-exit fees and charges. It also allows for preparatory expenditure to be incurred to prepare for withdrawal from the EU.

6. Part 5 places new powers on the Queen’s Printer for Scotland to publish retained (devolved) EU legislation.

7. Part 6 contains general and final provisions.

8. The Bill contains a provision allowing it not to be implemented if the Scottish Government and UK Government come to an agreement on Legislative Competence Motion.

Note on the Joint Ministerial Committee (European Negotiations), 22 February 2018 A proposal for a replacement to clause 11 was shared with the devolved administrations, and is likely to be tabled in the House of Lords. Shortly. UKG have indicated their hope that agreement can be reached with the devolved administrations on the basis of this amendments so that legislative consent can be recommended.

However this replacement for clause 11 contains a power allowing the UK Government unilaterally to restrict devolved competence in areas of EU law, with only consultation with the Scottish Ministers required, not with the consent of the Scottish Government or the Scottish Parliament. The devolved administrations acknowledged that there has been some shift in position from UKG but have indicated that further work is required on clause 11. Both devolved governments are in agreement that “consultation’ is not sufficient - the amendment must indicate either the requirement for ‘agreement’ or ‘consent’.

The Scottish and Welsh Governments will continue to develop alternatives to the UKG proposal for consideration in early discussion between the governments.