presidential system

A presidential system, also called a congressional system, is a system of government where an executive branch exists and presides (hence the term) separately from the legislature, to which it is not accountable and which cannot in normal circumstances dismiss it. It owes its origins to the medieval monarchies of France, England and Scotland in which executive authority was vested in the Crown, not in meetings of the estates of the realm (ie. parliament): the Estates-General of France, the Parliament of England or the Estates of Scotland. The concept of separate spheres of influence of the executive and legislature was copied in the Constitution of the United States, with the creation of the office of President of the United States. Perhaps ironically, in England and Scotland (since 1707 as the Kingdom of Great Britain, and since 1801 as the United Kingdom) the power of a separate executive waned to a ceremonial role and a new executive, answerable to parliament, evolved while the power of the USA's separated executive increased. This has given rise to criticism of the United States presidency as an "imperial presidency" though some analysts dispute the existence of an absolute separation, referring to the concept of "separate institutions sharing power".
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