In September 2019, Prime Minister Boris Johnson prorogued Parliament — suspended it for five weeks — in the middle of the Brexit crisis, preventing MPs from scrutinising his plans. The Supreme Court ruled the prorogation unlawful, and Parliament reconvened. But the fact that a Prime Minister could even attempt such a move revealed a fundamental flaw in the UK constitution: there are no clear, written rules to stop governments from abusing their power.
The UK is one of only three countries in the world without a codified written constitution (the others are New Zealand and Israel). Instead, the UK relies on an "unwritten" constitution — a patchwork of Acts of Parliament, conventions, common law, and historical precedent. This system is praised for its flexibility, but it is also dangerously unclear, easy to manipulate, and incapable of protecting citizens from government overreach.
It is time for Britain to join the rest of the democratic world and write the rules down.
What Is the UK Constitution?
The UK constitution is not a single document. It is a collection of sources:
1. Acts of Parliament
Laws passed by Parliament, such as:
- Magna Carta (1215) — limited the power of the monarch
- Bill of Rights (1689) — established parliamentary sovereignty
- Parliament Acts (1911, 1949) — limited the power of the House of Lords
- Human Rights Act (1998) — incorporated the European Convention on Human Rights into UK law
- Fixed-term Parliaments Act (2011) — set five-year parliamentary terms (later repealed in 2022)
These Acts can be amended or repealed by a simple majority in Parliament. There is no special protection for constitutional laws — they can be changed as easily as any other law.
2. Conventions
Unwritten rules that are followed by tradition but are not legally enforceable. Examples include:
- Collective cabinet responsibility — Cabinet ministers must publicly support government decisions or resign
- The Sewel Convention — Westminster will not normally legislate on devolved matters without the consent of the Scottish Parliament, Welsh Senedd, or Northern Ireland Assembly
- The Salisbury Convention — the House of Lords will not block legislation promised in the government's manifesto
- Royal Assent — the monarch always gives assent to bills passed by Parliament (the last refusal was in 1708)
Conventions are powerful, but they can be ignored. Boris Johnson broke the Sewel Convention by passing Brexit laws affecting devolved areas without consent. The Supreme Court ruled this was legal, because conventions are not law.
3. Common law
Judge-made law, developed over centuries through court decisions. Common law principles include the rule of law, judicial independence, and the presumption of innocence.
4. EU law (until Brexit)
Until 2020, EU law was part of the UK constitution, and EU law took precedence over UK law. Brexit ended this, but some EU-derived laws remain on the statute book.
The Problems with the Unwritten Constitution
1. It is unclear
No one knows exactly what the UK constitution says. Is the Sewel Convention legally binding? Can the Prime Minister prorogue Parliament? Can the government ignore a vote of no confidence? The answers are unclear, and disputes must be resolved by courts, which are not always equipped to answer political questions.
This lack of clarity creates constitutional crises, as in 2019 when the Supreme Court had to rule on whether prorogation was lawful.
2. It is easy to change
Because constitutional laws are just ordinary Acts of Parliament, they can be changed by a simple majority. A government with a large majority can rewrite the constitution to suit itself.
Examples:
- The Fixed-term Parliaments Act (2011) was passed to prevent Prime Ministers from calling elections at politically convenient times. Boris Johnson repealed it in 2022, restoring the Prime Minister's power to call elections.
- The Human Rights Act (1998) incorporated the European Convention on Human Rights into UK law. The Conservative government has threatened to repeal it and replace it with a "British Bill of Rights," which could weaken protections.
In most democracies, constitutional changes require a supermajority (e.g., two-thirds of Parliament) or a referendum. In the UK, a government with 326 MPs (out of 650) can change the constitution overnight.
3. Conventions can be ignored
Conventions are not law, so they can be broken without legal consequence. Boris Johnson broke the Sewel Convention, and there was nothing Scotland or Wales could do about it. Theresa May broke the convention that the government should resign if it loses a vote of no confidence (she stayed in office for months after losing a confidence vote in January 2019, arguing that the vote was not a formal motion of no confidence).
Conventions only work if everyone agrees to follow them. When a government decides to ignore them, there is no enforcement mechanism.
4. It concentrates power in the executive
The UK constitution gives enormous power to the executive (the Prime Minister and Cabinet), with few checks and balances. The Prime Minister can:
- Prorogue Parliament (suspend it)
- Call elections (since the repeal of the Fixed-term Parliaments Act)
- Appoint and dismiss ministers at will
- Make treaties without parliamentary approval
- Declare war without a vote (though by convention, Parliament is usually consulted)
A Prime Minister with a large majority can do almost anything, because Parliament is sovereign and the executive controls Parliament. This is what Lord Hailsham called an "elective dictatorship" — a government with near-absolute power, constrained only by the next election.
5. It does not protect rights
The UK has no Bill of Rights entrenched in a written constitution. The Human Rights Act (1998) incorporated the European Convention on Human Rights into UK law, but it can be repealed by a simple majority. If a future government wants to weaken human rights protections, it can.
In countries with written constitutions (the US, Germany, South Africa), rights are protected by the constitution and cannot be easily removed. In the UK, rights are only as strong as Parliament wants them to be.
The Case for a Written Constitution
A written constitution would:
1. Provide clarity
A single document would set out the rules of government, the powers of Parliament, the rights of citizens, and the limits on executive power. This would end constitutional uncertainty and reduce the need for courts to resolve political disputes.
2. Limit government power
A written constitution could impose checks and balances on the executive, such as:
- Requiring a supermajority to change the constitution
- Limiting the Prime Minister's power to prorogue Parliament or call elections
- Requiring parliamentary approval for treaties and declarations of war
- Protecting devolution by making it harder for Westminster to override devolved governments
3. Protect rights
A written constitution could include a Bill of Rights, protecting freedoms like speech, assembly, privacy, and fair trial. These rights would be entrenched, meaning they could not be removed by a simple majority.
4. Strengthen democracy
A written constitution could reform undemocratic institutions like the House of Lords (which is unelected) and introduce proportional representation to make elections fairer.
5. Restore trust
The UK public has lost trust in politicians and institutions. A written constitution, agreed by referendum, could restore legitimacy and provide a shared set of values and rules.
The Case Against a Written Constitution
Critics argue that:
1. Flexibility is a strength
The unwritten constitution can adapt quickly to changing circumstances. A written constitution is rigid and difficult to change, which can be a problem in a crisis.
For example, the US Constitution is notoriously difficult to amend (requiring two-thirds of Congress and three-quarters of states), which has left it stuck with outdated provisions (like the Second Amendment on gun rights).
2. It would give judges too much power
A written constitution would give courts the power to strike down laws that violate the constitution (as in the US). Critics argue this is undemocratic, because unelected judges would have the final say on what Parliament can do.
Supporters of parliamentary sovereignty argue that Parliament should be supreme, not judges.
3. It is unnecessary
The UK has been a stable democracy for centuries without a written constitution. Why fix what is not broken?
4. It would be difficult to agree
Writing a constitution requires consensus on fundamental questions: What rights should be protected? How should Parliament be elected? Should the monarchy be abolished? These are deeply divisive questions, and reaching agreement would be difficult.
How It Could Happen
Writing a UK constitution would require:
- A constitutional convention — a body of citizens, experts, and politicians tasked with drafting a constitution.
- Parliamentary approval — the draft constitution would need to pass both Houses of Parliament.
- A referendum — the public would vote on whether to adopt the constitution.
This process would take years and require a government willing to limit its own power, which is rare. No government wants to tie its own hands.
The most likely trigger for constitutional reform is a crisis — a government abuse so egregious that the public demands change. The 2019 prorogation crisis was close, but not quite enough.
Examples from Other Countries
United States
The US Constitution (1787) is the world's oldest written constitution. It sets out the powers of the President, Congress, and the courts, and includes a Bill of Rights. It is difficult to amend (requiring two-thirds of Congress and three-quarters of states), which has made it rigid and outdated in some areas.
Germany
The German Basic Law (1949) was written after World War II to prevent another dictatorship. It includes strong protections for human rights, limits on executive power, and a Constitutional Court that can strike down laws. It has been amended over 60 times, showing that written constitutions can be flexible.
South Africa
The South African Constitution (1996) was written after apartheid and is considered one of the most progressive in the world. It includes strong protections for equality, social rights (like housing and healthcare), and minority rights.
The Bottom Line
The UK is one of only three countries without a written constitution, relying instead on Acts of Parliament, conventions, and common law. The unwritten constitution is flexible but unclear, easy to change, and incapable of protecting citizens from government overreach. Boris Johnson's 2019 prorogation of Parliament exposed the system's flaws, and conventions like the Sewel Convention can be ignored without legal consequence. A written constitution would provide clarity, limit government power, protect rights, and strengthen democracy, but it would also be difficult to change and could give judges more power. The case for a written constitution is strong, but reform would require a government willing to limit its own power, which is rare. The UK has been a stable democracy for centuries without a written constitution, but stability is not the same as justice or accountability. It is time to write the rules down, protect rights, and ensure that no government can abuse its power again. The unwritten constitution is failing, and Britain deserves better.