What is the Principle of Separation of Powers, and What Does It Mean?

What is the Principle of Separation of Powers, and What Does It Mean?

June 26, 2021 Off By Felso

The separation of powers is a model that regulates the democratic state administration, put forward by the French enlightened thinker Baron de Montesquieu. In the separation of powers model, the state is divided into various units, each unit has separate and independent power and areas of responsibility. In addition, each unit can impose limitations on the use of power by the other. State departments generally consist of the legislature, the executive and the judiciary. According to the US system, these units are called “government units”, while in other systems “government” refers only to the executive unit.

Supporters of the separation of powers principle argue that this principle protects democracy and prevents tyrannical, totalitarian governments. According to the opponents of this principle, aside from protecting democracy, the separation of powers also slows down the administration and/or supports the executive dictatorship; It lowers accountability and undermines the power of the legislature.

Although it is not possible to talk about a fully implemented separation of powers or a union of forces today, many administrative systems are clearly based on the principle of separation of powers or unity of powers.


Montesquieu divided political power into three as legislative, executive and judicial. He based his idea on the British form of government. According to this, power was shared between the king, parliament and courts in the British administrative system. According to later writers who criticized Montesquieu, Montesquieu erroneously made such a justification because in Great Britain at that time the legislature, the executive, and the judiciary were interrelated.


While arranging the democratic management system, a certain choice is made between the Presidential system and the Parliamentary system, this election does not have to be a choice of order to be fully implemented. “Separation of powers” is more natural for presidential systems, “union of powers” is for “parliamentary systems”. However, there are also “mixed systems”, the system of government closer in the middle of the two main systems, for example the current form of government in France (5th Republic).

According to the principle of unity of forces, one administrative unit (usually elected legislative unit) is superior to the others and other units serve this unit. According to the principle of separation of powers, each unit is largely (although not completely) independent. Independence means that each unit is chosen independently from other units, or at least its existence is not dependent on other units.

Accordingly, in union of forces systems (for example, in the UK, for example) the legislature is elected by the people, and the legislature then “creates” the executive branch government. In systems of separation of powers, members of the executive branch are not elected by the legislature but by various other means (for example, by elections). In parliamentary systems, when the legislative branch expires, the executive branch also expires.

In presidential systems, the term of the executive unit is not dependent on the legislative term, its terms may or may not expire at the same time. The important point here is that the election of the executive branch is independent of the legislative branch. However, if the party of the executive branch has a majority in the parliament, a certain degree of “joined forces” effect can also be seen in the presidential system. Such situations can hinder constitutional goals and/or undermine the widely held idea that “the legislative body is more democratic, closer to the people”. In this case, the legislature simply takes the position of an “advisory council” and may be reluctant to hold the executive accountable for mistakes and failures.


To prevent one unit from being superior to another and to encourage units to work together, management systems that enforced separation of powers developed “brakes and balances”. This term is also attributed to Montesquieu. Thanks to the system of brakes and balances, some units can influence other units (for example, the US president has the right to veto laws passed by Congress, or Congress can change federal court decisions). Every country that has adopted the principle of separation of powers has its own system of “brakes and balances”. The closer the country’s government is to the presidential system, the more checks are between the units and the more equal are the units in terms of relative strength.

According to Montesquieu, every state has a legislature that makes laws and supervises their implementation, an executive that implements these laws, and a judiciary that punishes those who do not obey the laws. There can be no freedom in a country where legislative, executive and judicial powers are concentrated in one hand. What Montesquieu advocates is not a legal separation of powers, but a separation of social and political powers. At that time, the king who held the executive power, the nobles trying to maintain his position in various intermediate institutions, and the people led by the strengthening bourgeoisie.