Landmark Cases

This lesson examines the landmark cases that have defined the role of the judiciary in UK politics. Understanding key judicial decisions is essential for the Edexcel A-Level Politics specification because these cases illustrate how the courts check government power, protect rights, and shape constitutional principles. Each case reveals the dynamic tension between the judiciary, Parliament, and the executive.

---

Why Do Landmark Cases Matter?

In the UK's uncodified constitutional system, judicial decisions play a particularly important role in establishing and clarifying constitutional principles. Without a single written constitutional document, much of the UK's constitutional framework is defined through case law — the accumulated decisions of judges in individual cases.

Landmark cases matter because they:

• Set legal precedents that bind lower courts and shape future decisions.
• Establish the boundaries of government power.
• Define the rights of citizens in relation to the state.
• Illustrate the balance of power between the judiciary, Parliament, and the executive.

---

Case 1: R (Miller) v Secretary of State for Exiting the EU (2017) — Miller I

Background