The constitutional system is a system in which the government works under and in accordance with the constitution, which at the same time limits and controls the power of that government. The Constitution, as the basic law of the United States, is superior to all ordinary acts of the legislature and it effectively limits the power of the government. Moreover, it divides and distributes political authority among the main organs of the government, which powers are formally specified in that document, and which affect one another.
In American Political system, the Constitution divides and distributes the powers of the federal government between the central government and governments of each state. The Constitution gives certain powers to the states and simultaneously prohibits them from exercising certain other powers, and at the same time it reserves certain other powers to the national government and prohibits it from exercising the others. As far as the national government is concerned, the Constitution divides the powers of the national government between the most important organs of that government, and gives each organ the legal right and motivation to check and restrain the powers of the other. In the United States the national government is divided into the House of Representatives and the Senate (the Congress), the President of the United States, and the U.S. courts with the Supreme Court at the top. Each of those organs has the right to control or oppose the actions of the other. The powers of each branch of the government, whether legislative, executive or judicial, are closely connected with each other, that is why each branch may intervene in the actions of the other and prevent the other from abusing its power. The nature and shape of American Constitutional System was strongly influenced by the ideas of seventeenth and eighteenth century philosophers, namely the French Montusquieu and the English John Locke.