Official Life: Government and the Law
Great Britain (the political unit made up of England, Scotland, Wales, and Ireland) is, officially, ruled by a sovereign with the advice of Parliament. Parliament, like the U.S. Congress, has two branches. The upper house is the House of Lords, which is primarily based on heredity. Members of the House of Commons are elected. The British government differs from that of the United States in having no absolute separation of powers between its legislative, executive, and judicial branches. The prime minister and the cabinet are members of Parliament; the House of Lords has ultimate judicial authority and operates (although only rarely) as the highest court of appeal.
England has no written constitution, although the term "British Constitution" is used to describe the accumulated laws and traditions that determine how the government operates and to define the relationship between individuals and the state. In the early nineteenth century the central government was primarily limited to foreign relations, defense, and justice. Its powers and activities grew rapidly during the Victorian period as it began to control domestic affairs and take responsibility for citizens' health and safety.
By 1837 the monarchy had taken its modern form. Formally, the queen selected the prime minister--but in actuality, her choice was determined by Parliament's political leaders. She was always kept informed of government business, but she no longer had any real power except for the moral and symbolic influence she was able to exercise.