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Paper 2 · The Constitution · UK-EU relationship

Brexit and the constitution, 2016 to 2023

The episode that restored the supremacy of statute, empowered the executive, pulled the courts into politics and strained devolution - all at once. The exam question: what did Brexit mean for the constitution?

The arc at a glance

2016Referendum
2017Parliament and courts
2018Executive empowered
2019Courts check executive
2020Sovereignty and strain
2023NI special status

Click any step to jump to it - the lit step is the one showing below. Brexit cut several ways at once. Green = strengthened or expanded · Amber = mixed or contested · Red = weakened or reversed.

The timeline

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Timeline tucked away while you test yourself. Close the quiz to bring it back.

2016

What happened. David Cameron's government held the EU referendum: 52% Leave, 48% Remain on a 72% turnout. Legally advisory but politically decisive; Cameron resigned the next morning.

What it shows. Popular sovereignty asserted itself over parliamentary sovereignty in practice. Referendum

2017

What happened. R (Miller) v Secretary of State 2017 (Miller 1): the Supreme Court ruled 8-3 that Theresa May's government needed an Act of Parliament to trigger Article 50, leading to the EU (Notification of Withdrawal) Act 2017.

What it shows. The prerogative cannot remove statutory rights - Parliament, not ministers, decides. Parliament and courts

2018

What happened. The European Union (Withdrawal) Act 2018 repealed the European Communities Act 1972, converted EU law into retained UK law, and gave ministers wide delegated powers.

What it shows. The supremacy of statute is restored, but the executive is handed sweeping power to rewrite law. Executive empowered

2019

What happened. R (Miller) v The Prime Minister 2019 (Miller 2, with Cherry): the Supreme Court ruled 11-0 that Boris Johnson's prorogation of Parliament was unlawful.

What it shows. The courts will check even the executive's prerogative in a political crisis. Courts check executive

2020

What happened. The UK formally left the EU on 31 January 2020 and the transition ended in December; the Internal Market Act 2020 overrode devolved objections.

What it shows. Sovereignty is recovered at the centre, but devolution is strained. Sovereignty and strain

2023

What happened. The Windsor Framework 2023 revised the Northern Ireland Protocol, keeping NI in the EU single market for goods.

What it shows. The Union's internal border problem persists - NI keeps a special status. NI special status

Roll up and down: use the arrows, scroll or swipe inside the box, the up and down keys, or click any step in the arc above.

The account: what changed?

Brexit's headline constitutional effect was the recovery of parliamentary sovereignty: the EU (Withdrawal) Act 2018 repealed the European Communities Act 1972, ending the supremacy of EU law. But the same Act handed ministers sweeping delegated powers to rewrite retained EU law, strengthening the executive.

The courts were drawn into the biggest political questions of the era. Miller 1 (2017) forced the government to seek parliamentary authority before triggering Article 50; Miller 2 (2019) ruled the prorogation of Parliament unlawful. Both policed process rather than dictating policy, but both showed the judiciary willing to constrain the executive at the constitutional limit.

Devolution was strained: the Internal Market Act 2020 overrode devolved objections, and the Northern Ireland Protocol - revised as the Windsor Framework in 2023 - left NI with a special status inside the EU single market for goods, a continuing source of tension within the Union.

The judgement line: Brexit cut several ways at once: it restored the supremacy of statute, strengthened the executive through delegated powers, activated the courts in Miller 1 and 2, and strained devolution. A single change that reshaped sovereignty, the executive, the judiciary and the Union together.
Turn it into an essay: which dates argue which way

The same events split by side. Build each paragraph around one point from each column, then judge.

Brexit's constitutional impact was profound

  • 2018 EU (Withdrawal) Act repealed the ECA 1972 - the supremacy of statute restored.
  • 2017 Miller 1 - the prerogative could not trigger Article 50; Parliament had to legislate.
  • 2019 Miller 2 - the courts struck down an unlawful prorogation.

The impact was double-edged, not a clean return of control

  • 2018 The same Act handed ministers sweeping delegated powers - the executive gained.
  • 2020 The Internal Market Act overrode devolved objections - the Union strained.
  • 2023 The Windsor Framework left NI with EU rules for goods - sovereignty incomplete.

The Miller cases sit on the "profound" side, but note they policed process rather than policy - a point a strong answer concedes before judging.

Quick check: ten questions
Question 1 / 10Score 0
Use it in the 30-marker

For "Evaluate the view that Brexit has had a significant constitutional impact", this timeline gives a theme per card. Sovereignty (ECA repeal) and the Miller cases argue the impact was profound; the executive's delegated powers and the strain on devolution show it was double-edged rather than simply a return of control. End each paragraph with an interim judgement.

Keep the dates precise: referendum 2016, Miller 1 2017, EU (Withdrawal) Act 2018, Miller 2 2019, exit 31 January 2020, Internal Market Act 2020, Windsor Framework 2023.

Put the timeline to work on the judgement grid.
Open the Brexit impact grid →