Democracy and the British constitution

The rule of law and the separation of powers

The rule of law is the principle that no one is above the law, whether that person is an ordinary citizen, a police officer, a minister or the monarch. Everyone must obey the same laws, and everyone has the right to the law's protection and to a fair hearing if accused of wrongdoing. Government itself can only act using powers that the law gives it, and its decisions can be challenged in court if it oversteps them. This idea, that power must be used lawfully and fairly rather than arbitrarily, sits behind most of what makes the British system of government accountable.

The separation of powers is the idea that the state's functions are best kept apart so that no single body controls everything. Three roles are usually distinguished: making laws, which belongs to Parliament; carrying laws out and running the country day to day, which belongs to the government; and interpreting the law and settling disputes, which belongs to the judiciary, meaning judges and the courts. In the UK these roles overlap more than in some other countries, since government ministers are themselves drawn from Parliament and remain answerable to it. What is kept firmly apart is the judiciary. Judges must be free from pressure by ministers or by Parliament so that they can decide cases only on the law and the facts, without fear of losing their post or their income for reaching an unwelcome verdict. This judicial independence is protected by law: senior judges can only be removed from office through a formal process involving both Houses of Parliament, not by a minister's decision, and judges are barred from standing for election to the House of Commons. The courts, in turn, can check the other branches: they can rule that a government body has acted outside its legal powers, and government departments must comply with such rulings. Parliament remains sovereign, so the courts cannot strike down an Act of Parliament itself, but they can and do hold ministers and public bodies to the law that Parliament has made.

The institutions that run the state

A number of long-standing institutions together run the United Kingdom, and each keeps a check on the others' power. They are the monarchy, Parliament with its two houses, the office of Prime Minister, the cabinet, the judiciary, the police, the civil service and local government. The devolved administrations in Scotland, Wales and Northern Ireland have been added to this structure more recently, taking on responsibility for certain matters in their own nations. These institutions, along with the laws and long-standing customs that govern how they work together, make up the British constitution.

The police form a distinct part of this structure. They enforce the law and keep public order, but they operate independently of government ministers, who cannot direct how officers police an individual case. This separation matters because it stops political interference in law enforcement and means the police must treat everyone the same way regardless of status or background. Officers who break the law themselves, for instance through corruption or abuse of their position, can be prosecuted and punished like anyone else, which is itself an expression of the rule of law.

The armed forces defend the country and support the government in operations overseas and at times of emergency at home, but they are not counted among the constitutional institutions that run the state, since their role is to serve and protect rather than to govern or make policy.