Fusion of powers in the context of "HM Government"

A parliament is the type of legislature, or law-making body, of a state based on the fusion of powers. Generally, a parliament has three functions: representing the electorate, making laws, and overseeing the executive government via hearings and inquiries. Its role is similar to that of a senate, synod or congress. The term parliament is commonly used in countries that are current or former monarchies. Some contexts restrict the use of the word to parliamentary systems, although it is also used to describe the legislature in some presidential systems (e.g., the Parliament of Ghana), even where it is not in the official name. A parliament is typically made up of elected members, who are legislators.

Historically, parliaments included various kinds of deliberative, consultative, and judicial assemblies. Parliamentary gatherings in the Middle Ages began to establish that monarchs were subject to law and first summoned representatives of common people, notably the Cortes of León in 1188 and an English parliament in 1265. During the early modern period, the Glorious Revolution of 1688 in Britain established the primacy of parliamentary sovereignty, through which the rule of law could be enforced. Many other modern concepts of parliamentary government developed subsequently in the Kingdom of Great Britain (1707–1800). Expansion of suffrage in the 19th and 20th centuries led to parliaments around the world becoming democratically elected.

The separation of powers principle functionally differentiates several types of state power (usually legislation, adjudication, and execution) and requires these operations of government to be conceptually and institutionally distinguishable and articulated, thereby maintaining the integrity of each. To put this model into practice, government is divided into structurally independent branches to perform various functions (most often a legislature, a judiciary and an administration, sometimes known as the trias politica). When each function is allocated strictly to one branch, a government is described as having a high degree of separation; whereas, when one person or branch plays a significant part in the exercise of more than one function, this represents a fusion of powers. When one branch holds unlimited state power and delegates its powers to other organs as it sees fit, as is the case in communist states, that is called unified power.

A parliamentary system, or parliamentary democracy, is a form of government based on the fusion of powers. In this system the head of government (chief executive) derives their democratic legitimacy from their ability to command the support ("confidence") of a majority of the parliament, to which they are held accountable. This head of government is usually, but not always, distinct from a ceremonial head of state. This is in contrast to a presidential system, which features a president who is not fully accountable to the legislature, and cannot be replaced by a simple majority vote.

Countries with parliamentary systems may be constitutional monarchies, where a monarch is the head of state while the head of government is almost always a member of parliament, or parliamentary republics, where a mostly ceremonial president is the head of state while the head of government is from the legislature. In a few countries, the head of government is also head of state but is elected by the legislature. In bicameral parliaments, the head of government is generally, though not always, a member of the lower house.

The supreme state organ of power (SSOP) is a type of legislature and the highest representative institution in communist states operating under the Marxist–Leninist principle of unified power. Unlike systems based on the fusion or separation of powers, the SSOP holds legislative, executive, judicial, and all other forms of state power. Formally regarded as the embodiment of popular sovereignty and the head of the unified state apparatus, its activities in practice are closely shaped by the ruling communist party.

The SSOP's theoretical origins trace back to Jean-Jacques Rousseau's idea of a “supreme power” of the people, Karl Marx’s call for unity of state power, and Vladimir Lenin’s vision of soviets as working organs which combined lawmaking and execution. The world's first SSOP was the All-Russian Congress of Soviets, established after the 1917 October Revolution, and it became the prototype for similar institutions in other communist states.

His Majesty's Government, abbreviated to HM Government or otherwise UK Government, is the central executive authority of the United Kingdom of Great Britain and Northern Ireland. The government is led by the prime minister (Keir Starmer since 5 July 2024) who selects all the other ministers. The government is currently supported by the Labour party, which has had a majority in the House of Commons since 2024. The prime minister and his most senior ministers belong to the supreme decision-making committee, known as the Cabinet.

Ministers of the Crown are responsible to the House in which they sit; they make statements in that House and take questions from members of that House. For most senior ministers this is usually the elected House of Commons rather than the House of Lords. The government is dependent on Parliament to make primary legislation, and general elections are held at least once every five years to elect a new House of Commons, unless the prime minister advises the monarch to dissolve Parliament, in which case an election may be held sooner. After an election, the monarch selects as prime minister the leader of the party most likely to command the confidence of the House of Commons, usually by possessing a majority of MPs.