The constitutional principle that limits the powers vested in any person or institution. It divides governmental authority into three branches: legislative (Parliament or Senate), executive (President or Prime Minister and the Cabinet), and judiciary (Chief Justice and other judges). This principle is expressed fully in the US Constitution, but is used only as a guide in the UK.
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Definition: The term separation of powers originated with the Baron de Montesquieu, a French enlightenment writer. However, the actual separation of powers amongst different branches of government can be traced to ancient Greece. The framers of the Constitution decided to base the American governmental system on this idea of three separate branches: executive, judicial, and legislative. The three branches are distinct and have checks and balances on each other. In this way, no one branch can gain absolute power or abuse the power they are given.
In the United States, the executive branch is headed by the President and includes the bureaucracy. The legislative branch includes both houses of Congress: the Senate and the House of Representatives. The judicial branch consists of the Supreme Court and the lower federal courts.
The division of state and federal government into three independent branches.
The first three articles of the U.S. Constitution call for the powers of the federal government to be divided among three separate branches: the legislative, the executive, and the judiciary branch. Under the separation of powers, each branch is independent, has a separate function, and may not usurp the functions of another branch. However, the branches are interrelated. They cooperate with one another and also prevent one another from attempting to assume too much power. This relationship is described as one of checks and balances, where the functions of one branch