Key Stage 4 citizenship · Democracy and government

GCSE citizenship: executive, legislature and judiciary

UK government is often explained as three separate roles. The legislature makes laws, the executive puts them into practice, and the judiciary decides what the law means and whether it has been followed. In Key Stage 4 citizenship, students learn who does each job, how the branches check one another and where they overlap, which is a key feature of the UK system.

Executive, legislature, judiciary, explained

The idea of dividing power between branches is called the separation of powers, and the aim is to stop any one person or group holding too much. In the UK the legislature is Parliament: the House of Commons, whose elected MPs have the final say on most laws, the House of Lords, whose members are not elected by the public and who examine and revise bills, and, formally, the monarch, who gives Royal Assent. Parliament debates, amends and passes laws, approves taxes and checks the government.

The executive is the part of government that runs the country day to day and puts laws into effect. It includes the Prime Minister, the Cabinet and other ministers, who lead government departments, and the civil service, whose members are politically impartial officials who advise ministers and carry out policy. Ministers make most of the big decisions, such as how money is spent, but they have to act within the law and explain themselves to Parliament. Local authorities, police forces and many public bodies carry out executive functions at a local level.

The judiciary is made up of judges and magistrates in the courts. Their job is to apply the law fairly, decide disputes, and, in criminal cases, decide the outcome of trials, often with a jury in the more serious ones. Judges are independent: they are appointed on merit, cannot easily be removed and should not be pressured by ministers. Since 2009, the UK Supreme Court has been the highest court for civil cases across the UK and for criminal cases in England, Wales and Northern Ireland. In Scotland the final court for criminal cases is the High Court of Justiciary. Judges can also review whether ministers have acted within the law, and they interpret Acts of Parliament, but they can’t strike them down.

What makes the UK system distinctive is that the branches overlap more than students expect. By convention, ministers are also members of the Commons or the Lords, so the executive sits inside the legislature, and the government usually controls the Commons through its majority. Until 2009 the most senior judges sat in the House of Lords; the Supreme Court was created to separate them. Teachers ask students to weigh up how much separation is enough: does the overlap make government more accountable, or does it concentrate power? Schools choose their own case studies for this, so expect varying examples from year to year.

Words your child will hear

Separation of powers: Dividing the powers of government between different branches so that no one person or group has all of them.
Legislature: The body that makes and changes laws. In the UK, this is Parliament.
Executive: The part of government that runs the country and puts laws into practice: the Prime Minister, ministers and the civil service.
Judiciary: The judges and courts, who apply the law and settle disputes independently.
Civil service: Politically impartial government employees who advise ministers and carry out their decisions.
Royal Assent: The monarch’s formal approval of a bill, which turns it into an Act of Parliament.
Judicial independence: The principle that judges make decisions free from pressure from politicians or others.

What the National Curriculum says

The programme of study for Key Stage 4 says:

Pupils should be taught about parliamentary democracy and the key elements of the constitution of the United Kingdom, including the power of government, the role of citizens and Parliament in holding those in power to account, and the different roles of the executive, legislature and judiciary and a free press
Teaching should build on the key stage 3 programme of study to deepen pupils’ understanding of democracy, government and the rights and responsibilities of citizens.

Objectives from the National Curriculum in England, © Crown copyright, used under the Open Government Licence v3.0.

Try it: tracing a law through the three branches

Imagine a new Act of Parliament that bans the sale of energy drinks to under-16s. Using this simplified example, decide which branch is acting at each stage.

A government minister decides to propose the ban and the department drafts a bill. This is the executive, because ministers and civil servants prepare and propose most legislation.
The bill is debated, amended and voted on in the Commons and the Lords. This is the legislature, because only Parliament can pass an Act.
The bill receives Royal Assent and becomes an Act. This is the final step of the legislature’s work, and by convention it is automatic, which keeps real decision-making with elected politicians.
Council trading standards officers check that shops follow the new rules, and ministers are responsible for how the policy works. This is the executive again.
A shopkeeper is prosecuted for selling a drink to a 15-year-old and argues that the drink isn’t covered by the Act. A court hears the case. This is the judiciary, which decides what the Act means and whether the law was broken.

The executive proposes and carries out the law, the legislature debates and passes it, and the judiciary settles disagreements about it. The branches check each other: Parliament can question ministers or reject their bill, and courts can rule that a minister has acted outside the law. They also overlap, because the ministers who propose the bill sit in Parliament and usually have the votes to pass it.

Common mistakes and how to help

“The Prime Minister makes the laws.”

The Prime Minister is so prominent in the news that it looks as if they decide everything. Government does propose most bills, but they only become law after Parliament passes them.

What helps: Ask who must agree before a bill becomes law: normally the Commons, the Lords and, formally, the monarch. A government with a majority often succeeds, but it still has to win the vote.

Thinking the monarch, the government and Parliament are the same thing

The three get used interchangeably in everyday talk, such as “the government passed a law”. The monarch is head of state, the government is the executive and Parliament is the legislature.

What helps: Ask your child to sketch who sits where: ministers on the government benches, other MPs and peers in the two Houses. A diagram helps to show that ministers have a foot in each.

Believing judges can overrule Parliament

Court rulings against the government make headlines, so students assume the judiciary has the final word. Courts can find that a minister acted unlawfully, and they can interpret laws, but they cannot strike down an Act of Parliament.

What helps: Distinguish between decisions made by ministers, which courts can review, and Acts of Parliament, which they must apply. Ask your child which one a judge reviewed in a news story.

Assuming the three branches are completely separate

Diagrams in textbooks show three neat boxes. The UK system is a blend, not a strict split.

What helps: Ask your child to find two overlaps, such as ministers sitting in Parliament, and the Lord Chancellor, a government minister who has a legal duty to protect judicial independence. Then ask whether overlap is a strength or a weakness, with a reason.

How to help at home

Sort the news into three piles. Read a few headlines and decide whether each is about the executive, the legislature or the judiciary. A story about a vote in the Commons, a new department policy and a court judgment will each land in a different pile.
Run a family version. Pick a household rule. Who proposes it, who agrees it, and who settles the argument when someone says it was broken unfairly? It makes the three roles feel real and shows why one person doing all three is risky.
Hold a mini-trial. Give your child an invented dispute, such as a rule about screen time, and ask them to play an impartial judge who must explain a decision using the rule as written. It shows why judges apply laws and don’t just invent them.
Debate the overlap. Ask: should ministers have to be MPs or peers? There are good arguments both ways. Ask your child to give one for each side with an example.

Builds on

Key Stage 3: How UK democracy developed
Key Stage 3: Citizens, Parliament and the monarch
Key Stage 3: How Parliament works
Key Stage 3: Voting and elections
Key Stage 3: The role of political parties

More on democracy and government

Everything in Key Stage 4 citizenship

Updated 20 October 2026.