The EU, Brexit, and Constitutional Implications

The UK's relationship with the European Union — from accession in 1973 to departure in 2020 — has been one of the most constitutionally significant issues of the modern era. Brexit raised fundamental questions about parliamentary sovereignty, the role of referendums, the status of international treaties, and the relationship between the Executive, Parliament, and the courts.

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The UK and the EU: A Constitutional History

Joining the EEC (1973)

The UK joined the European Economic Community (EEC) on 1 January 1973 under the European Communities Act 1972 (ECA). This Act gave EU law direct effect in UK law and established the supremacy of EU law over domestic legislation in areas of EU competence.

The Constitutional Impact of EU Membership

EU membership had profound constitutional effects: