Constitution of Estonia is the fundamental law of the Republic of Estonia and establishes the state order as that of a democratic republic where the supreme power is vested in its citizens. The first Constitution was adopted by the freely elected Estonian Constituent Assembly on 15 June 1920 and came into force on 21 December 1920. Heavily amended on 24 January 1934, following a referendum in 1933, it was in force until the second Constitution was enacted on 1 January 1938. It remained in force, de facto, until 16 June 1940, when the Soviet Union occupied Estonia and, de jure, until 28 June 1992, when the fourth and current Constitution of the Republic of Estonia was adopted by referendum.
The first Constitution was a reflection of Jean-Jacques Rousseau's idea of national sovereignty. Power was split between the judiciary, the executive and the legislature according to the principles of Montesquieu. The Constitution provided for a high degree of public initiative and for referendums. Despite the Constitution being modelled upon Montesquieu's ideas, there was an imbalance in the distribution of power. The document was radically parliamentarian, vesting the single-chamber Riigikogu with extensive power over the executive and the judiciary, leading to instability and frequent changes of government. A State Elder, a post equivalent to that of president, served as both head of state and head of government.
Due to chronic government instability (18 governments headed by 10 State Elders), attempts were made to redraft the Constitution. In a referendum held in 1932, voters rejected two proposed drafts of a new Constitution, but a constitutional amendment, proposed by the populist Estonian War of Independence Veterans' League or Vaps Movement was adopted in a referendum in 1933 and came into force on 24 January 1934. This amendment, which vested broad powers in the State Elder while reducing the size and power of the Riigikogu, had such a vast impact on the governing system that it is frequently mistaken for a new constitution in its own right. The State Elder had the power to issue decrees with the force of law. In order to prevent the Vaps Movement coming to power under this new Constitution, Konstantin Päts, who was serving as "Prime Minister in Duties of the State Elder" pending elections, seized power in a bloodless coup d'etat on 12 March 1934. Believing that the amended constitution was too authoritarian, Päts pressed for the adoption of a new Constitution.
In 1936, a referendum approved the formation of a National Assembly to draft a replacement document. This Constitution, which came into force on 1 January 1938, created a bicameral National Assembly, consisting of the Chamber of Deputies and the National Council. The National Council, which was to review and ratify legislation from the Chamber of Deputies, consisted of representatives from local government, professional and vocational bodies, and high officials, while the Chamber of Deputies was directly elected by the people. The head of state was given the title of "President"; he was no longer directly elected by the people, but instead was chosen by an electoral college consisting of both chambers of the National Assembly and additional representatives of local government. The President was vested with fairly broad powers, but was somewhat less powerful than the State Elder under the 1934 amendments.
A Soviet-style "constitution" was introduced illegally, not having been subjected to referendum as required by the third Constitution, by a Soviet-backed puppet government on 25 August 1940. It was based on the 1936 Soviet constitution. The Soviet Estonian 1940 constitution was replaced by another constitution in 1978, based on the 1977 Soviet constitution.
The present Constitution was enacted after a referendum on 28 June 1992. It incorporates elements of the Constitutions of 1920 and 1938. While retaining the presidency created in 1938, it restores the unicameral legislature established in 1920. It explicitly asserts its continuity with the Estonian state as it existed between 1920 and 1940, and thus provides a restitutive basis for Estonia's independence. Like the 1920 Constitution, the head of state--titled as President after some debate about restoring the old title of State Elder--is a largely ceremonial post. However, like the 1938 Constitution, the government is headed by a separate Prime Minister.
The current Constitution contains a preamble and several chapters. The Preamble reads:
The current Constitution contains fifteen chapters.
For the celebrations of the fifteenth anniversary of the current Constitution, A. Le Coq produced a new brand of beer, the Constitutional Pilsener (Estonian: Põhiseaduse Pilsner) in cooperation with the Estonian Ministry of Justice.