He was from France and at that time France was ruled by a Tyrant King. He saw people in his country in deplorable condition as a result. On the other hand, he visited many countries where people enjoyed great freedom and liberty and concluded that their happiness was a result of separation of powers in the government of those countries. He presented his doctrine of separation of powers in his famous book, The Spirit of Laws in 1748. In his book he explained his theory in the following words;- "In every government there are three sorts of power: legislative, executive and judicial. The liberty of individual requires that neither all these powers nor any two of them should be placed in the hands of one man or one body of men. When the legislative and executive are united in the same person or body of person, there can no liberty, because apprehension may arise that the king, who is also the law-make might end up making and enforcing law in a tyrannical manner. He further stated that if the judicial power is joined with the legislative power, the life and liberty of the people would be exposed to arbitrary control, for the judge would then be the legislator and would interpret laws as he pleases. If the judicial power is joined to the executive power, the judge might behave with violence and oppression and, there would be an end of everything if the same man or the same body, were to exercise those powers that of enacting law, that of enforcing them and of trying the cases of individuals.
Many English writers and thinkers imitated him in their own way and we can see the perfect example of the doctrine of separation of powers in England. The English jurist, Blackstone, expressed the idea of separation of powers in the following words: "Whenever the right of making and enforcing the law is vested in the same man or one and the same body of men, there can be no public liberty.
In Britain also, there are various authorities who hold some degree of power but not absolute power. These authorities are: Royal Crown, Parliament, Prime Minister and his cabinet, judicial system of Britain. All these constitute different forms of powers, which we are going to discuss in the later part of our essay.
The powers that are held by the Royal Crown are contained in a body of laws known as "Royal Prerogative". These are actually formal powers that are granted to the Britain's Royal Crown in the executive and British politics. However, one must remember all the time that even these powers are not absolute powers and are checked by many limitations upon them. The following powers are given to the Royal Crown, and if we analyze them in detail, we will find out that the principle of separation of powers even apply to the Royal Prerogative. For example, The Queen reigns over Britain and chooses and dismisses the Primer Minister. However, she cannot choose just anyone for the post of Prime Minister, but only after the election are held, only then she could choose the leader of the party securing majority in the party as the Prime Minister of Britain. This law limits her powers that she cannot own on her own accord but instead she only acts on the accord and willingness of general public. In theory, the Royal Preroga