Judiciary & Executive
This lesson examines the relationship between the judiciary and the executive in UK politics. The judiciary's role in checking executive power through judicial review is one of the most important safeguards in the UK constitutional system. This topic is essential for the Edexcel A-Level Politics specification, particularly questions about the balance of power between the branches of government.
The Executive and the Law
The executive (the Prime Minister, Cabinet, and government departments) exercises enormous power in the UK political system. The executive:
- Proposes and implements legislation
- Manages public services
- Conducts foreign policy
- Commands the armed forces
- Exercises prerogative powers (powers inherited from the Crown)
However, the executive must act within the law. The rule of law requires that every action of the government must have a legal basis — either in statute (an Act of Parliament) or in the royal prerogative. If the government acts without legal authority, its actions are ultra vires and can be struck down by the courts.
Key Term: The executive must always act within its legal powers. Judicial review is the mechanism by which the courts enforce this requirement.
How Does the Judiciary Check the Executive?
1. Judicial Review of Executive Decisions
Judicial review is the primary mechanism by which the judiciary checks the executive. Courts can examine whether:
- A government minister had the legal power to make a particular decision (illegality).
- The decision was rational — that no reasonable decision-maker would have reached it (irrationality).
- The decision was made following a fair procedure (procedural impropriety).
- The decision was proportionate — not going further than necessary (proportionality, particularly in human rights cases).
Example: In R (on the application of UNISON) v Lord Chancellor (2017), the Supreme Court held that the Lord Chancellor's decision to impose employment tribunal fees was unlawful because it effectively denied access to justice — a constitutional right.
2. Reviewing the Exercise of Prerogative Powers
The royal prerogative refers to powers that the Crown (in practice, the government) exercises without the need for parliamentary authorisation. These include:
- Declaring war and deploying armed forces
- Negotiating and signing treaties
- Granting pardons
- Proroguing Parliament
Historically, prerogative powers were considered non-justiciable — the courts would not review how they were exercised. However, the landmark GCHQ case (1985) changed this by establishing that prerogative powers are, in principle, subject to judicial review.
The Miller cases pushed this further:
- Miller I (2017): The Supreme Court ruled that the government could not use prerogative power to trigger Article 50, because this would remove rights conferred by statute.
- Miller II (2019): The Supreme Court ruled that the Prime Minister's advice to prorogue Parliament was justiciable and unlawful.
These cases significantly expanded the scope of judicial oversight of prerogative powers.
3. Enforcing Human Rights
Under the Human Rights Act 1998, the judiciary can check the executive by:
- Declaring executive actions unlawful if they are incompatible with Convention rights (Section 6 HRA).
- Interpreting legislation in a way that is compatible with Convention rights (Section 3 HRA).
- Issuing declarations of incompatibility if primary legislation is incompatible with Convention rights (Section 4 HRA).
Example: In the Belmarsh case (2004), the House of Lords ruled that the executive's policy of indefinitely detaining foreign terror suspects was incompatible with the ECHR. The government was forced to replace detention with a system of control orders.
Key Case Studies: Judiciary vs Executive
Miller I — Article 50 (2017)
- Issue: Could the government trigger Article 50 using prerogative power alone?
- Decision: No — only Parliament could authorise the removal of statutory rights. The Supreme Court ruled 8-3 against the government.
- Significance: Confirmed that the executive cannot use prerogative to override statute. Reinforced parliamentary sovereignty.
Miller II — Prorogation (2019)
- Issue: Was the Prime Minister's advice to prorogue Parliament for five weeks lawful?
- Decision: No — the prorogation was unlawful, void, and of no effect. Unanimous 11-0 decision.
- Significance: Established that the courts can review the exercise of the prorogation prerogative. Demonstrated the Supreme Court's willingness to rule on the most politically sensitive executive actions.
GCHQ Case (1985)
- Issue: Could the government ban trade unions at GCHQ (Government Communications Headquarters) using prerogative power?
- Decision: The House of Lords held that prerogative powers are in principle reviewable by the courts, though in this specific case, national security justified the government's decision.
- Significance: Opened the door for judicial review of prerogative powers — previously considered beyond the courts' reach.
Belmarsh Case (2004)
- Issue: Was the indefinite detention of foreign terror suspects compatible with human rights?
- Decision: No — the detention was incompatible with Articles 5 and 14 of the ECHR. Declaration of incompatibility issued.
- Significance: Demonstrated that the courts will challenge the executive on national security policy when fundamental rights are at stake.
AAA v Secretary of State — Rwanda (2023)
- Issue: Was Rwanda a safe country for the deportation of asylum seekers?
- Decision: No — the Supreme Court ruled unanimously that Rwanda was not safe, due to the risk of refoulement.
- Government response: The Safety of Rwanda Act 2024, legislatively declaring Rwanda safe.
- Significance: Illustrated the executive's ability to use Parliament to override judicial findings, raising questions about the limits of government power.
Government Responses to Adverse Judicial Decisions
When the executive disagrees with a judicial ruling, it has several options: