Chapter 5 Answers to quick test questions

Parliamentary sovereignty, the European Union, and Brexit

1. What are the aims of the EU?

Under TEU Art 1 the broad aim of the EU is stated to be ‘an ever closer union among the peoples of Europe’. This is achieved through pursuing the objectives of the EU. These include in particular the completion of the internal market, Member States adopting the single European currency and providing EU citizens a common area of freedom, security and justice.

2. Which cases established the supremacy of EU law? 

The main case that established the supremacy of EU law is Costa v ENEL. Here, the European Court of Justice found that certain provisions of the Italian Constitutional Code were contrary to articles of the EC Treaty. On this basis, the ECJ held that the Treaty was directly enforceable in the Member States and, to ensure uniformity and consistency across the union, it should take precedence over measures of domestic law.

Other cases coming after Costa and adding weight to the principle were Internationale Handelsgesellschaft mbH v Einfuhr und Vorratsstelle für Getreide und Futtermittel and Ammistrazione delle Finanze dello State v Simmenthal SpA.

3. What are the key provisions of the European Communities Act 1972 and what was their effect? 

The key provisions and their effect in the UK constitution are as follows:

    - Section 2(1). This provides that ‘[a]ll such rights, powers, liabilities, obligations and restrictions from time to time created or rising by or under the Treaties … are without further enactment to be given legal effect … in the United Kingdom’. It is as a result of this section, therefore, that EU law is given effect in the UK.

    - Section 2(4). This works alongside section 2(1) in requiring the UK courts to interpret domestic law in line with provisions of EU law.

4. What are the facts underpinning the Factortame litigation? Why was the House of Lords’ judgment so significant?
The Merchant Shipping Act 1988 changed the criteria for fishing vessels wishing to fish in British waters. One of the new requirements was that all such vessels be based in and managed from within the UK. Factortame Ltd, a Spanish company, challenged this, arguing that it was contrary to EU law.

The significance of the case, and of the House of Lords’ judgment, is that the 1988 Act was disapplied in preference to EU law. This amounted to a limitation on the sovereignty of Parliament, effectively requiring its enactments to be consistent with EU law.

5. What is the distinction, with regard to implied repeal, between ordinary and constitutional statutes?

Laws LJ, in Thoburnv Sunderland City Council, explained ‘We should recognise a hierarchy of Acts of Parliament: as it were ‘ordinary’ statutes and ‘constitutional’ statutes … Ordinary statutes may be impliedly repealed. Constitutional statutes may not’.1

6. What was the basis of the Supreme Court’s decision in Miller

In R (Miller) v Secretary of State for Exiting the European Union, a majority of the Supreme Court held that the Government could only trigger Article 50 – thereby setting in motion the Brexit process – with parliamentary approval. The basis for this view was that EU law is an ‘independent and overriding source of domestic law’ which cannot be changed without parliamentary involvement.2 Such fundamental changes to the constitutional arrangements of the UK, they said, could not be effected by government Ministers alone.


The main consequence of the decision was the enactment of the European Union (Notification of Withdrawal) Act 2017, which gave the Prime Minister the power to trigger Article 50, which she did on 29th March 2017.

7. What are the main aims of the European Union (Withdrawal) Act 2018? 

As originally enacted, the main intention of the European Union (Withdrawal) Act was to prepare the UK legal system for Brexit. Primarily, the 2018 Act sought to achieve this by providing that on the day the UK leaves the EU, the European Communities Act 1972 will be repealed, and that EU law that has become part of UK law under the Act will remain part of UK law, but as ‘retained EU law’. The aim was to ensure that legal continuity is maintained. Then gradually, individual laws could be repealed or amended by the UK Parliament, as the UK would no longer be bound by EU law as it is no longer a member.

8. What amendments did the European Union (Withdrawal Agreement) Act 2020 make to the European Union (Withdrawal) Act 2018 so that the 2018 Act takes account of the transition period, as provided for by the Withdrawal Agreement?

As required by TEU Art 50, the EU and UK agreed the Withdrawal Agreement, which sets out the terms on which the UK has left the EU. This took effect on 31st January 2020. The most important element of the Withdrawal Agreement is the transition period. During the transition period, although no longer a member of the EU, the UK remains bound by EU law. The transition period last from 31st January 2020 to 31st December 2020, but it can be extended to last until the end of 2021 or 2022. The intention is that at the end of the transition period, the future and ongoing relationship between the UK and the EU will have been negotiated and will take effect.

This means that to give effect to the Withdrawal Agreement, the European Union (Withdrawal Agreement) Act 2020 which implements the Withdrawal Agreement into UK law, needed to amend the European Union (Withdrawal) Act 2018. It does this in two key ways. Firstly, although formally the European Communities Act 1972 has been repealed, new sections are inserted into the 2018 Act, retaining the effect of the 1972 Act for the duration of the transition period. This means that because EU law is still part of UK law, the provisions of the 2018 Act which provide for retained EU law are amended by the 2020 Act so that they only take effect at the end of the transition period.

1 [2002] EWHC 195 (Admin) [62] – [63]

2 [2017] UKSC 5 [81] and [82]