The Three Branches of US Government

U.S. Capitol building
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The United States has three branches of government: the executive, the legislative and the judicial. Each of these branches has a distinct and essential role in the function of the government, and they were established in Articles 1 (legislative), 2 (executive) and 3 (judicial) of the U.S. Constitution.

The Executive Branch

The executive branch consists of the president, vice president and 15 Cabinet-level departments such as State, Defense, Interior, Transportation and Education.

The primary power of the executive branch rests with the president, who chooses his vice president, and his Cabinet members who head the respective departments. A crucial function of the executive branch is to ensure that laws are carried out and enforced to facilitate such day-to-day responsibilities of the federal government as collecting taxes, safeguarding the homeland and representing the United States' political and economic interests around the world.

The Legislative Branch

The legislative branch consists of the Senate and the House of Representatives, collectively known as the Congress. There are 100 senators; each state has two. Each state has a different number of representatives, with the number determined by the state's population, through a process known as "apportionment." At present, there are 435 members of the House. The legislative branch, as a whole, is charged with passing the nation's laws and allocating funds for the running of the federal government and providing assistance to the 50 U.S. states.

The Judicial Branch

The judicial branch consists of the United States Supreme Court and lower federal courts. The Supreme Court's primary function is to hear cases that challenge the constitutionality of legislation or require interpretation of that legislation. The U.S. Supreme Court has nine Justices, who are chosen by the President, confirmed by the Senate.

Once appointed, Supreme Court justices serve until they retire, resign, die or are impeached. 

The lower federal courts also decide cases dealing with the constitutionality of laws, as well as cases involving the laws and treaties of the U.S. ambassadors and public ministers, disputes between two or more states, admiralty law, also known as maritime law, and bankruptcy cases. Decisions of the lower federal courts can be and often are appealed to the U.S. Supreme Court.

Checks and Balances

Why are there three separate and distinct branches of government, each with a different function? The framers of the Constitution did not wish to return to the totalitarian system of governance imposed on colonial America by the British government.

To ensure that no single person or entity had a monopoly on power, the Founding Fathers designed and instituted a system of checks and balances. The president's power is checked by the Congress, which can refuse to confirm his appointees, for example, and has the power to impeach, or remove, a president. Congress may pass laws, but the president has the power to veto them (Congress, in turn, may override a veto). And the Supreme Court can rule on the constitutionality of a law, but Congress, with approval from two-thirds of the states, may amend the Constitution.

Phaedra Trethan is a freelance writer and a former copy editor for The Philadelphia Inquirer newspaper.