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EU referendum: UK proposals, legal impact of an exit and alternatives to membership

Published Friday, February 12, 2016

This paper considers the background to the EU referendum, the withdrawal process, various legal and constitutional issues and possible alternatives to EU membership. What might the impact be of a decision to leave the EU? How would the UK leave? Would the UK join a different grouping of states or go it alone? Would EU or UK citizens or businesses have any vested rights?

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David Cameron pledged during the previous Parliament that if the Conservatives were returned to government in the 2015 general elections, he would legislate to hold an in out referendum on the UK’s continued membership of the European Union, following the negotiation and agreement of a number of reforms he had set out in speeches and policy papers.

The UK will hold a referendum on whether to stay in the European Union by the end of 2017, after the Government has negotiated reforms which will benefit the UK. The Prime Minister outlined his proposed reforms to the European Council in June 2015.

The first pro- and anti-EU membership campaigns were launched in October 2015.

Parliamentary process


The Prime Minister’s speech at Bloomberg on 23 January 2013 identified areas for reform and in March 2014 he set out the following proposals for reform:

  • Powers flowing away from Brussels, not always to it
  • National parliaments able to work together to block unwanted EU legislation
  • Businesses liberated from red tape
  • UK police forces and justice systems able to protect British citizens, without interference from the European institutions
  • Free movement to take up work, not free benefits
  • Removing the concept of “ever closer union”

The UK reform agenda was launched – briefly – at the European Council on 25-26 June 2015. This triggered the start of technical talks, which were held in secret, involving UK and EU officials.

The referendum on UK membership of the EU: assessing the reform process, was published by the House of Lords European Union Committee on 28 July 2015.

Donald Tusk’s draft texts to address the UK demands

The Prime Minister published his proposed reforms in a letter to European Council President Donald Tusk in November 2015.

The European Council in December 2015 did not make much progress on the UK reform proposals and further discussion was scheduled for a European Council meeting in February 2016. The EU and UK negotiators continued discussions and the Prime Minister embarked on further talks with EU governments.

On 3 February 2016 the European Council President Donald Tusk published six draft documents intended to address UK concerns. These are the basis for intensified negotiations with a view to reaching agreement in February 2016.

Parliamentary reports

Implications of leaving the EU

As to whether UK citizens would benefit from leaving the EU, this would depend on how the UK Government filled the policy gaps left by withdrawal from the EU.

What would happen to individuals and businesses who were already exercising EU rights – either in the UK or in other EU countries – if the UK left the EU?

Some of these ‘vested’ rights might not be automatically removed or reversed once the EU Treaties no longer applied, either because of a withdrawal agreement, or because some EU-based UK legislation would probably remain in force.

In some cases it might not be compatible with domestic law (and/or international law) to remove vested EU rights.

The Commons Library published a Briefing Paper called Exiting the EU: impact in key UK policy areas, (up-dated 12 February 2016)

EU Treaty provisions on withdrawal from the Union

Article 50 of the treaty on European Union provides for a Member State to leave the EU, either on the basis of a negotiated withdrawal agreement or without one.

If the UK were to leave the EU following a referendum, it is likely that the Government would negotiate an agreement with the EU, which would probably contain transitional arrangements as well as provide for the UK’s long-term future relations with the EU.

There is no precedent for such an agreement, but it would in all likelihood come at the end of complex and lengthy negotiations.

Pros and cons of EU membership

There is no definitive study of the economic impact of the UK’s EU membership or the costs and benefits of withdrawal. Many of the costs and benefits are subjective or intangible and a host of assumptions must be made to reach an estimate.

If the UK were to remain in a reformed EU, assumptions need to be made about what the reforms might be. Any estimate of the effects of withdrawal will be highly sensitive to such assumptions.

In some policy areas – the environment, for example – where the UK is bound by other international agreements, much of the content of EU law would probably remain. In others, it might be expedient for the UK to retain the substance of EU law, or for the Government to remove EU obligations from UK statutes.

Alternatives to EU membership

Much would also depend on whether the UK sought to join the European Free Trade Association (EFTA), remain in the European Economic Area (EEA) and therefore continue to have access to the single market, or preferred to go it alone and negotiate bilateral agreements with the EU along the lines of the Swiss model.

Further information

Publication details

Commons Briefing papers CBP-7214

Authors: Vaughne Miller; Arabella Lang; Ben Smith; Dominic Webb; Daniel Harari; Matthew Keep; Paul Bowers; Richard Cracknell

Topics: EU law and treaties, EU political integration, Europe, International economic relations, International law, International politics and government

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