Factual and Procedural Background
On Wednesday 28 August 2019, at a Privy Council meeting held at the Court at Balmoral, Her Majesty ordered that Parliament be prorogued from a date between 9 and 12 September until 14 October 2019, on the advice of the Prime Minister. Proceedings challenging this decision were initiated the same day. The principal issue was whether the Prime Minister's decision to seek prorogation was justiciable or an exclusively political matter. After hearing arguments on 5 September, the court concluded the decision was not justiciable and dismissed the claim, while granting permission for judicial review and allowing a leap-frog appeal to the Supreme Court if leave to appeal was granted.
Parallel proceedings were ongoing in Scotland, initiated earlier due to concerns about prorogation around the statutory Brexit exit date of 31 October 2019. The Scottish Outer House dismissed the claim on similar grounds, and an appeal was underway in the Inner House. The court reviewed the Scottish judgment.
Oral arguments were heard from counsel representing the claimant and the Prime Minister. Numerous applications to intervene were received, with four accepted in writing from significant political and governmental figures supporting the claimant. The court acknowledged the assistance of all parties and interveners under a tight timetable.
Legal Issues Presented
- Is the Prime Minister's decision to advise the Sovereign to prorogue Parliament justiciable in the courts of the United Kingdom?
- If justiciable, was the advice to prorogue Parliament lawful or an unlawful abuse of power?
Arguments of the Parties
Appellant's Arguments
- The Prime Minister's advice to prorogue Parliament was an unlawful abuse of power motivated by improper considerations, notably to prevent Parliament from holding the Government to account and from passing legislation to avoid a no-deal Brexit.
- The decision breached the constitutional principle of Parliamentary Sovereignty by impeding Parliament’s ability to legislate and scrutinise during a critical period.
- The prerogative power to prorogue Parliament is subject to judicial review, and the courts have a duty to intervene where there is a manifest abuse of power.
- The length of the prorogation was excessive and unjustified, further evidencing improper purpose.
- There are legal standards applicable to the exercise of the prorogation power, and the courts should assess whether those standards have been breached.
Interveners' Arguments
- The Shadow Attorney General argued that Parliamentary Sovereignty requires that prorogation powers be constrained within constitutional limits to prevent frustration of Parliament’s functions, including the ability to vote on motions of no confidence.
- The Counsel General for Wales emphasized the importance of judicial supervision to secure executive accountability and legislative autonomy, especially given the Welsh Government’s interest in ongoing legislative dialogue with Westminster.
- A former Prime Minister submitted that it is unlawful to prorogue Parliament to obstruct its legislative functions or to prevent it convening to debate important issues, and that the length of prorogation was disproportionate and politically motivated.
- The Lord Advocate highlighted that the timing and duration of prorogation had a disproportionate impact on accountable government, with no compelling justification, effectively insulating the Government from scrutiny.
Respondent's Arguments
- The decision to prorogue Parliament was inherently political and involved no legal standards against which the courts could judge its legitimacy.
- The prorogation was justified by a combination of practical, legal, and political considerations, including preparation for the Queen’s Speech, the long preceding parliamentary session, and the traditional conference recess.
- There is no legal or constitutional measure of the appropriate length of prorogation, and the courts lack jurisdiction to assess the reasonableness of its duration.
- Parliamentary Sovereignty means the Queen in Parliament is sovereign in enacting primary legislation, but does not confer a legal right to uninterrupted parliamentary sitting or prevent prorogation.
- The courts must respect the separation of powers and refrain from intervening in matters of high policy or political judgment.
Table of Precedents Cited
| Precedent |
Rule or Principle Cited For |
Application by the Court |
| Council of Civil Service Unions v Minister for the Civil Service [1985] AC 374 (CCSU) |
Exercise of prerogative powers is subject to judicial review depending on subject matter, not source. |
Confirmed that prerogative powers may be justiciable but political matters are generally non-justiciable. |
| R (Miller) v Secretary of State for Exiting the European Union [2018] AC 61 (Miller No.1) |
Statutory authority is required for triggering Article 50; affirmed principle of Parliamentary Sovereignty. |
Referenced in relation to Parliamentary Sovereignty and statutory limits on prerogative powers. |
| R v Secretary of State for the Home Department, ex p. Bentley [1994] QB 349 |
Justiciability of grant of pardons under prerogative powers. |
Illustrated courts’ willingness to review certain prerogative exercises affecting individual rights. |
| Lewis v Attorney General of Jamaica [2001] 2 AC 50 |
Prerogative of mercy is justiciable. |
Supported extension of judicial review to prerogative powers once considered non-justiciable. |
| R v Secretary of State for Foreign and Commonwealth Affairs, ex p Everett [1989] QB 811 |
Refusal of passports subject to judicial review. |
Demonstrated limits of non-justiciability in foreign affairs where individual rights are affected. |
| R (Sandiford) v Secretary of State for Foreign and Commonwealth Affairs [2014] 1 WLR 2697 |
Judicial review of foreign relations decisions affecting individuals. |
Approved the principle that some prerogative decisions are reviewable. |
| R (Youssef) v Secretary of State for Foreign and Commonwealth Affairs [2016] AC 1457 |
Judicial caution in reviewing foreign relations prerogative powers. |
Clarified that not all prerogative exercises are non-justiciable; individual rights may warrant review. |
| R (Bancoult) v Secretary of State for Foreign and Commonwealth Affairs (No. 2) [2009] AC 453 |
Justiciability of Orders in Council made under prerogative powers. |
Confirmed courts can review Orders in Council where appropriate standards exist. |
| Mohammed (Serdar) v Minister of Defence [2017] AC 649 |
Justiciability of prerogative powers in defence matters. |
Supported the principle of subject matter determining justiciability. |
| A v Secretary of State for the Home Department [2005] 1 AC 68 |
Political questions are generally non-justiciable; courts defer to political resolution. |
Provided guidance on the limits of judicial intervention in political matters. |
| Gibson v Lord Advocate 1975 SC 136 |
Courts do not decide political matters; focus on individual rights and obligations. |
Reinforced the separation of powers and limits on judicial review. |
| Robinson v Secretary of State for Northern Ireland [2002] UKHL 32 |
Political judgment in constitutional arrangements is generally non-justiciable. |
Emphasized the flexible political nature of certain constitutional decisions. |
| Shergill v Khaira [2015] AC 359 |
Non-justiciability arises from lack of judicial standards and political nature. |
Supported the principle that political questions lack manageable legal standards. |
| Wheeler v Office of the Prime Minister [2008] EWHC 1409 (Admin) |
Political judgments about treaties and referenda are non-justiciable. |
Demonstrated courts’ reluctance to engage in political judgments without legal standards. |
| McClean v First Secretary of State [2017] EWHC 3174 (Admin) |
Political agreements and decisions lack legal standards for judicial review. |
Confirmed political nature of certain government agreements precludes judicial intervention. |
| British Railways Board v Pickin [1974] AC 765 |
Parliamentary Sovereignty as a fundamental constitutional principle. |
Referenced in relation to the scope and limits of Parliamentary Sovereignty. |
| R (UNISON) v Lord Chancellor [2017] 3 WLR 409 |
Rule of Law and access to justice principles constraining executive action. |
Used to discuss limits on executive power in relation to Parliamentary Sovereignty. |
| Jackson v Attorney General [2006] 1 AC 262 |
Interpretation and scope of Parliamentary Sovereignty. |
Clarified the nature of Parliamentary Sovereignty within the UK constitutional framework. |
| Bobb v Manning [2006] UKPC 22 |
Political judgment in constitutional matters is entitled to deference. |
Supported the proposition that political discretion in executive decisions is lawful. |
Court's Reasoning and Analysis
The court began by reaffirming the established principle that exercises of the Royal Prerogative are not immune from judicial review per se; rather, reviewability depends on the subject matter. Powers involving "high policy" or inherently political decisions—such as treaty-making, dissolution or prorogation of Parliament—are generally non-justiciable due to the absence of judicially manageable standards.
The court extensively analysed the nature of prorogation, distinguishing it from dissolution and adjournment, and noted its historical and statutory context. It recognised that prorogation ends all parliamentary business until a new session begins, effectively suspending Parliament's legislative and scrutiny functions.
The court considered the claimant’s argument that the prorogation was an abuse of power aimed at frustrating Parliament’s sovereignty and accountability functions during a critical period before the Brexit deadline. While acknowledging the gravity of these concerns and the submissions of interveners supporting the claimant, the court found that the decision to prorogue was political in nature with no legal standards applicable for judicial scrutiny.
The court rejected the claimant’s proposed broader legal conception of Parliamentary Sovereignty that would render prorogation subject to judicial review based on its length and purpose. It held that such an expansion would intrude upon the constitutional separation of powers and the political domain, which is governed by statute and convention rather than judicial oversight.
The court observed that Parliament retains multiple mechanisms to assert its authority, including the ability to pass legislation rapidly when it chooses, as demonstrated by the swift enactment of legislation shortly after prorogation. It also noted that there is no legal or constitutional rule prescribing the permissible length of prorogation.
Ultimately, the court concluded that the Prime Minister’s advice to prorogue Parliament was a political decision, involving considerations such as legislative preparation and party conference recesses, and was therefore non-justiciable. It emphasized the importance of maintaining the separation of powers and respecting the political nature of such executive decisions.
Holding and Implications
The court's final decision was to DISMISS THE CLAIM, holding that the Prime Minister's advice to Her Majesty to prorogue Parliament was not justiciable in the courts of the United Kingdom.
The direct effect of this decision is that the prorogation order stands and the courts will not intervene in the political exercise of prorogation powers. The court did not establish any new legal precedent expanding judicial review over prerogative powers in this context, reaffirming the established constitutional principle that political decisions of this nature lie outside judicial scrutiny. The ruling preserves the separation of powers and maintains the political accountability of the executive to Parliament rather than to the courts.