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Separation of Powers in the United States

This article explores the separation of powers on the federal level in the United States. Power is divided between three branches: the executive, the legislative, and the judiciary branch. The US Constitution defines what power each branch has, and also how the branches relate to each other.
A short summary of the text
  • In the United States, there is a federal level and a state level of government.

  • At the federal level, power is divided between three branches. They are called 'the executive branch', 'the legislative branch', and 'the judicial branch'.

  • The executive branch does the day-to-day running of the country, the legislative branch makes laws and controls the budget, the judicial branch reviews and interprets laws.

  • Each branch has the power to check the actions of the other branches.

  • The reason power has been separated between three branches is to limit the risk of corruption and abuse of power.

A state level and a federal level

This article focuses on separation of powers on the federal level. The federal government is also called the US government; it is the government for the whole country. However, you should be aware that each of the 50 states in the US has its own government, and most states separate powers into a state executive, a state legislative, and a state judicial branch. A governor plays the same role at the state level as the president does at the federal level.

The states have a lot of freedom to run and rule themselves without interference from the federal government. The federal government has been assigned power over areas where it is more convenient for the 50 states to work together than it is for each state to solve a challenge alone.

The Constitution has given certain powers to the federal government. These are called enumerated powers or expressed powers. These powers include the rights to collect taxes, regulate foreign and domestic commerce, coin money, declare war, support an army and navy, and establish lower federal courts.

Study the illustration of the three branches of the US government before you read on.

A system of checks and balances

It was the French philosopher Charles Montesquieu who first proposed a system of separation of powers. He believed that if power was allocated to one person, or a small group of people, it would inevitably lead to abuse of power, and the rights of the citizens would not be safeguarded. He believed that it was better to divide power between different branches and give those branches the power to control each other's work. We call this a system of checks and balances. Dividing power is intended to prevent corruption and abuse of power.

The Founding Fathers did not want to replace the rule of a powerful British king with the rule of a powerful American president, so they wrote a constitution that keeps individuals from getting too much power. This system provides citizens with the comfort that actions and decisions will be discussed and debated before they are approved by the elected officials.The United States was the first country to implement this system, and it has inspired countless other countries to follow in their footsteps.

In the system of checks and balances there is an executive branch that governs the country, a legislative branch that makes the laws and controls the budget, and a judicial branch that interprets the laws and safeguards the civil liberties of the citizens.

Study the illustration of how the different branches of the US government check and balance each other before you read on.

The executive branch

The president is elected by the people as the leader of their country. Since America is a super-power, the president's has a great deal of influence also outside the United States. The president is the head of the executive branch. The executive branch governs the country and enforces laws. It includes the president, the vice president, the cabinet, and executive departments. The president also appoints people to a number of important offices. The president is often called 'the most powerful person in the world', and while there is some truth to that, there are important limits to a president's power.

In order to be able to govern the country, the executive branch has to create a budget and get approval for the budget. Only Congress can approve the budget. The president and the government may propose laws, but only Congress can pass them, and laws passed by Congress may be struck down by the Supreme Court. The president may veto a bill passed by Congress. If a president vetoes a bill it is returned to Congress, where it will take a two-third majority vote in both the Senate and the House to overrule the president's veto and make it a law. The president may choose a candidate for the Supreme Court, but the candidate must be confirmed by the Senate. The president is commander-in-chief, but the power to declare war formally belongs to Congress.

If a president does something wrong they may be impeached. For impeachment procedures to begin, the House of Representatives must first vote to agree that an impeachment trial is to be held. At the trial, the Chief Justice of the Supreme Court presides, and a two-thirds majority vote in the Senate is required to convict. If convicted, the president will no longer be president. Only three US presidents have ever been impeached, but none have been convicted. President Trump is the only president to have been impeached twice.

The legislative branch

The legislative branch is elected by the people. In the United States, the legislative branch is made up of the Congress and several government agencies. Congress is divided into two houses: the House of Representatives and the Senate.

As the name suggests, the legislative branch legislates: it makes laws. In addition, the legislative branch controls the budget. Formally, only Congress may declare war, but they have not done so since 1942.

A law passed by Congress may be overturned by the Supreme Court if the court believes the law is unconstitutional. The president can veto laws passed by Congress. Congress can override the veto by a two-thirds majority vote in both the House of Representatives and the Senate.

The judicial branch

The head of the judicial branch is the Supreme Court. There are also other federal courts that are part of the judicial branch. The judicial branch reviews and interprets the laws.

The Supreme Court can overturn laws if they are perceived to be unconstitutional. This is called judicial review. If Congress wants to pass such a law, they will first have to change the Constitution.

When someone is put on trial for a crime, the courts must find out whether they have broken the law: this is one situation in which the judicial branch interprets laws.

There are nine Supreme Court justices. Congress has the power to determine how many Supreme Court justices there should be, but the number has been nine since 1869.

Members of the Supreme Court are appointed by the president and confirmed by the Senate.

The Supreme Court can declare presidential acts unconstitutional.

Supreme Court justices serve for life, as do other federal judges. A Supreme Court justice may be impeached. This is done through a two-thirds majority vote in the House of Representatives, and a trial and conviction by the Senate. Only one Supreme Court Justice has ever been impeached.

An independent judicial branch is important to safeguard the freedoms and rights of the citizens.

Study the illustration of how the different branches of the US government are elected.

Quiz:

What do you remember?

Learn more about the American system of government

These websites can help you learn more about the American system of government.

  • Visit each page to see what it can offer you. Then choose one to explore more fully.

  • Make yourself a fact sheet about the political system in the United States.

Website: the US government


This is a website made by the US government dedicated to explaining the system of government in the United States. The site contains a lot of interesting information and illustrations.


Link to website about the government in the United States of America.


Website: Benjamin Franklin's guide to the US government


This is a website developed by the US government. The site is intended for children. It contains fun and easy interactive exercises where you can check your understanding of the system of government in the United States.

Link to Bensguide: A children's website about the U.S. government


Website: Khan Academy


This is an educational website that provides educational material for free. The link leads to an introduction to the American system of separation of powers.

Link to Khan Academy: Principles of American Government.

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