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Constitutional history of

Known as Siam until 1939, Thailand lies in the heart of Southeast Asia. It is bordered by Laos, Burma, Cambodia and Malaysia, and has an expansive coastline on the Andaman Sea and the Gulf of Thailand. The country spans 198,000 sq miles (the world's 51st largest country) and has a population of approximately 65 million (the world's 20th most-populous country). About 75% of the population is ethnically Thai, 14% are Chinese, and the remaining 11% is made up of Malay, Mons, Khmers and other tribes. Thailand is a devoutly Buddhist country. Its national religion is Theravada Buddhism, which is practiced by approximately 95% of the population.

Constitutional history

In the mid-nineteenth century, Thailand transitioned from a feudal state into an emerging nation-state as it opened its economy to foreign trade. Slavery and serfdom were eliminated, which instigated the breakdown of some traditional hierarchies and prompted judicial and legal reform. The absolute monarchy, however, persisted until a coalition of civil servants and army officers seized power in a bloodless coup in 1932, established Thailand's first constitution, and instituted a constitutional monarchy. Despite aspirations to shift to democratic rule, the country struggled to reconcile the ideals of Western constitutionalism with the realities of Thai society, namely a highly stratified culture with a largely uneducated population, where political and economic resources concentrated in the hands of the few. For example, the 1932 constitution stipulated that all representatives would eventually be elected, but such requirement was conditional on half the electorate having completed primary education.

Since the coup of 1932, Thailand has had 17 constitutions and charters, with a series of intervening military coups. All have been under the construct of a constitutional monarchy but, until recently, have been viewed largely as conduits for facilitating the power and advantage of the dominant political faction of the time. During the first several decades of the constitutional monarchy, various rival factions vied for power, often resorting to the use of force. Maintaining government stability proved increasingly difficult. From 1947 to1958, there were seven attempts to overthrow the government by force, four of which succeeded in changing the government. New leaders often sought legitimization and stability by writing new constitutions, thus promulgating a persistent cycle of: (i) military coups usurping power, (ii) new leaders suspending constitutions and then legitimating their power with new constitutions until (iii) a perceived crisis leads to another coup.

From 1957 to 1992, the Thai constitution continued to undergo many revisions as power continued to change hands. The political elites regularly criticized the Western concept of constitutionalism, and the executive branch was often empowered at the expense of the legislature and the judiciary. In particular, the regime of Sarit Thanarat (1959-1963) became very paternalistic, invoking what he claimed to be the ancient practices of Thai kings, in the process curtailing or prohibiting several democratic institutions.

Recent Constitution Building

The Constitution of 1997 was initiated by Thai citizens. The seed for change was planted in May of 1992 during “Black May”, an uprising of mainly members of the middle-class, which mobilized the public around demands for profound political and social reform. A Constitution Drafting Assembly (CDA), consisting of ninety-nine members, seventy-six of which were elected from all provinces, was appointed to rewrite the constitution. Termed the People's Constitution, the 1997 constitution received high praise, from within Thailand as well as internationally, for the participative nature of its drafting, support of human rights and advances in political reform. One of the most significant changes made was in the shift from representative democracy to participatory democracy, achieved through public participation in the process of appointment of independent commissions as well as the Election Commission, the Administrative Court and the Ombudsman. Other innovations occurred in the separation of the executive and legislative branches, election reform, recognition of human rights and increased checks and balances.

A political crisis that spanned 2005 to 2006 eventually resulted in another coup and shift of political power. Thailand has long struggled with a growing urban-rural divide, abuses of power, and the lack of freedom for the media. It was, however, the corruption charges against Prime Minister Thaksin Shinawatra that sparked mass demonstrations and an eventual coup on September 9, 2006. In the wake of the coup, the military junta took power. The King announced that he had revoked the 1997 Constitution and placed the junta in charge of the country. The junta, now called the Council for Democratic Reform, was tasked with creating the new constitution. Later that month, they released an interim constitution.

Provisions of the Interim Constitution

The Interim Constitution was meant only to be a tool for allowing the junta to maintain control of the government while the new constitution was created. While it mandated that the new constitution had to be approved by referendum, it also provided that the constitution drafters would be appointed by the junta itself. It also allowed the junta to establish its one permanent constitution unilaterally if the draft constitution was rejected. The junta Council for Democratic Reform was renamed the Council for National Security. This Council retained most of the power in the interim government, even though the monarch was deemed the head of state and the armed forces. A prime minister was also to be appointed, along with a 35 member Council of Ministers. The Prime Minister could only be removed by the monarch with the consent of the chairman of the Council for National Security. This executive branch was therefore divested of much of its power, and the Council for National Security retained its power of maintaining the public order and national security. The legislative branch, or national assembly, was tasked with creating bills and directives, but only relating to activities dealing with its own procedures. The 250 members were also appointed by the king, not elected. The Interim Constitution basically kept in place the judiciary system of the 1997 Constitution, which created a Constitutional Tribunal, tasked with settling disputes over the Interim Constitution. Its seven judges were selected by the other sitting judges through a secret ballot.

There was some controversy surrounding the drafting of the new, permanent constitution by the committee selected by the National Assembly. The selection of committee members was fraught with turmoil, voting irregularities, and claims of bribery. Almost immediately, the committee was faced with pressure to include specific provisions in the new constitution. Different political, religious, and social groups attempted to bribe, sway, and threaten the committee into including provisions which protected or advanced their particular interests. For example, the leader of a Thai Buddhist group threatened to instruct his followers to reject the new draft if Buddhism was not declared the national religion. One of the biggest issues facing the committee was how much power to assign to the Prime Minister. In the aftermath of the coup and corruption charges against the last Prime Minister, many called for curbing the power of the executive to prevent a recurrence of recent events. There was also some difficulty in deciding just how many officials were to be elected, and how many were to be appointed in the new national government, as the junta struggled with its dueling desires to retain power and create a democratic constitution.

The Public Consultation Process

In July of 2007, the committee released the draft for public circulation, and the national debate began. The government ran a national advertising campaign aimed at drumming up support for the proposed constitution. This campaign was sharply criticized, however, for using national media outlets as propaganda tools. Additionally, the draft was distributed throughout the country, but was not translated into Malay for the southern peoples, who were subsequently unable to understand the contents of the draft. The government also offered free transportation to the polling stations for rural peoples, but this was also criticized as the government had been conducting a heavy campaign among the countryside by going door-to-door to educate voters on the referendum. Many saw this as the government’s attempt to rig the voting. Finally, the government passed an act forbidding opposition or criticism of the draft, and imitation campaigns were conducted throughout the country. There were also accusations of vote-buying on both sides, but in spite of all this, the referendum passed by 59.3% of the vote on 19 August 2007.

Constitutional Changes

The 2007 Constitution of Thailand imposes many restrictions on the executive branch. It declares that one may only be Prime Minister for 8 years. Additionally, it places restrictions on the Prime Minister’s family by requiring them to declare all assets and forbidding them to have a hand in any companies. These provisions are aimed directly at the allegations against the former Prime Minister, as are the provisions granting the public more power to submit laws and seek transparency. Fewer people are now required to propose a law, and citizens may now directly petition the Senate to dismiss the Prime Minister and other officers. Local governments are also required to make greater efforts at transparency by submitting plans and budgets to the locals, and they must continue to report on progress and implementation.

Some of the most important provisions, however, are the different agencies created in the Constitution to oversee the politics of Thailand. Each of these agencies is directed at ensuring the allegations of rampant corruption which sparked the 2006 coup do not reoccur. The first of these organizations is the Election Commission. The three members of the Commission are appointed by the King with the advice of the Senate. However, the real power of appointment comes from the Selective Committee whose members are selected by the Presidents of the highest Courts and the House, the leader of the opposition in the House, and two people chosen respectively by the Supreme Court of Justice and the Supreme Administrative Court. The Senate then approves the nominations, and the King officially appoints them. The Commissioners hold their office for seven years, and they oversee national and local elections, as well as referendums. It is their purpose to ensure that all elections are honest and fair. In the years since the passing of the Constitution, their decisions have been instrumental in the ever changing and turbulent political landscape of Thailand. It is their duty to investigate any claims made against candidates for office, and if too many complaints are deemed valid against a certain political party, the party may be disbanded or the election re-held.

The Ombudsman has a similar power of review over government officials. They are also appointed by the King with the advice and consent of the Senate, with the power to conduct investigations into the dealings of government officials to ensure that they are carrying out their duties in a lawful, ethical manner. If they discover that an official has violated a law, acted in an unethical manner, or has failed to carry out his duties, the Ombudsman may submit the case to the Constitutional or Administrative Courts for review. The Ombudsman acts in conjunction with the National Counter Corruption Commission. This Commission, also appointed by the King with the advice and consent of the Senate, searches for corruption among government officials. Members of the House and Senate may submit allegations to the Commission, but they may also lodge allegations against the Commission itself with the Senate to seek removal of an Officer or with the Supreme Court of Justice to seek a trial.

The Constitution does, however, have some significant innovations. While it does not provide for a wholly elected Senate, it no longer contains the earlier proposal creating a National Crisis Council that would have given the military significant control over the administration of the government in times of national crisis. It also contains more provisions regarding human rights. Unlike the Interim Constitution or the 1997 Constitution, this document allows the courts to look directly to the Constitution itself to determine the rights of the people. Older documents had required reference to other documents like legislative acts, which could be amended or discarded. This Constitution also allows people to directly submit constitutional challenges to the Constitutional Court. It also gives more power to the courts by allowing high-ranking judges to be on committees which select candidates for the Senate and independent agencies.

The Constitutional System

The 2007 Constitution put into place a Constitutional Monarchy. The King remains the Chief of State, but the Prime Minister is the head of the government. This means that the King has little direct power, and acts more as a respected figure head than a governing official. He is nominally the head of the Armed Forces, and the protector of all faiths in the country. He also retains some traditional powers such as the appointment of heirs and the power to grant pardons. The King may, if he so chooses, appoint 18 Councilors to his Privy Council of 18 Councilors which assists him directly. These Councilors are removable only by the King, and they act as his personal advisors in all matters relating to the King’s duties.

The Prime Minister is selected through an election in the lower house, and is usually the head of the prevailing party in the national elections. He is then officially appointed by the King and heads the executive branch. The Prime Minister is charged with presenting the public face of the government in both foreign and domestic affairs. Similarly, the King appoints another 35 Ministers to comprise the Council of Ministers. This Cabinet creates policies for the administration of the government and execution of the laws, but it is accountable to the Legislature for its actions.

The Legislature is bicameral, with a partially elected Senate and a fully elected House of Representatives. Thailand has multiple parties, but the Communist Party is prohibited. In total, the legislature contains 630 members. The Senate has 150 members, 74 of whom are appointed by the Senate Selection Commission. The Senate has fairly limited legislative powers, but is in charge of scrutiny and appointment. The Senate cannot be dissolved, and Senators sit for six year terms. The other 400 members of the legislative branch sit in the House. Eighty percent of these representatives are appointed according to the proportion of party representation. The rest are elected by a popular vote. The House has the true legislative power, and it may also remove the Prime Minister and Cabinet Ministers through a vote of no-confidence. While House members sit for four year terms, the lower chamber can be dissolved by the King at any time before the end of that term.

The highest court of Thailand is the Constitutional Court. This nine judge panel is selected in various ways. Three members are elected by the Supreme Court of Justice from among its ranks. Two are similarly elected from the Supreme Administrative Court. The final four are not judges prior to obtaining this post. The Constitution mandates that two of these members must be legal professionals, while the other two members must be in the fields of political science, public administration, or social sciences with a background in public affairs. These four judges are selected by the Selective Committee comprised of the other judges of the Constitutional Court, the Presidents of the House majority and minority, and the President of the Constitutional independent organizations. The Senate then approves the nomination, and the King officially appoints them to the Court. The judges are empowered to hear cases pertaining to constitutional issues, whether they are raised in the progress of a case, or submitted for review by private persons. The Court, however, may refuse to hear the petition or case. Additionally, the Court may resolve disputes between branches of government.

System of Government under 2007 Constitution


Political Challenges

Issues Challenges
  • Government transparency and accountability
  • Urban-rural divide – how to equalize the benefits of economic development and ensure equal political representation?
  • Corruption
  • Violent protests between political groups


1932 Bloodless coup removes monarch from power, constitutional monarchy and parliamentary government introduced
1947 Military coup by pro-Japanese Phibun Songkhram
1973 Student riots in Bangkok results in fall of the military government and free elections
1976 Military coup
1978 New constitution passed
1980 Military coup by General Prem Tinsulanonda
1983 General Prem gives up military position to head civilian government
1988 Election replace Prem with General Chaticha Choonhaven
1991 17th military coup since 1932 sees civilian Anand Panyarachun installed as Prime Minister
1992 Mass protests against the results of the election that replaced Anand with General Suchinda Kraprayoon force his resignation and new election of Chuan Leekpai
1995 After government collapse, Banharn Silpa-archa elected Prime Minister
1996 In the wake of corruption charges, Banharn government resigns and Chavalit Yongchaiyudh elected
1997 Asian financial crisis, Chuan Leekpai replaces Chavalit as Prime Minister
January 2001 Thaksin Shinawatra wins elections amid vote-buying allegations and forms coalition government
2004 Ethnic tensions grow after attacks on Muslims lead to more than 100 deaths
2005 After his reelection, Thaksin given new powers to quell the unrest by suspected Muslim militants in the south
19 September 2006 Military leaders stage bloodless coup and retired General Surayud Chulanont appointed interim Prime Minister
2007 Referendum approves a new military-drafted constitution and Thaksin’s party banned from politics, though its reincarnation party wins elections
2008 Samak Sundaravej becomes Prime Mininster amongst bloody mass protest clashes between pro and anti government demonstrators
2009 Protests continue among Thaksin supporters
2010 Pro-Thaksin protestors shut down Bangkok for two months to demand the resignation of the Prime Minister, but army troops end the demonstrations after negotiations fail




  • Chief of State
  • Head of the Armed Forces
  • Protector of Faiths
  • Pardons and appointment of heirs
  • Appointment of a 18 member Privy Council which advises the King
  • Upon end of 5-year term (prolongable in case of war or catastrophe)
  • Upon removal initiated by the parliament and after conviction by the supreme court of justice
  • Upon resignation

Prime Minister

Elected by House of Representatives and appointed by King
  • Approval of appointments
  • Head of Government
  • Public face of the Government at home and abroad
  • Upon vote of no confidence by House of Representatives
  • Upon loss of or resignation from qualifying position as member of ruling political party


  • Appointed by the King
  • Advising the Monarch in the exercise of his duties
  • Acting as a member of the Conference of Rulers
  • Appointing parliamentary secretaries
  • Overseeing the Cabinet
  • Upon vote of no confidence by the House of Representatives



  • 74 members appointed by the Senate Selection Commission
  • 76 members elected
  • Scrutiny of the government
  • Appointment of government officials
  • Upon end of 6 year term
  • Upon resignation

House of Representatives

  • 320 members appointed according to party elections
  • 60 elected by direct vote
  • Introduces and passes laws
  • Votes of no confidence in Prime Minister and Cabinet
  • Upon end 4 year term
  • Upon dissolution by the King
  • Upon resignation


Constitutional Court

  • 3 judges elected by and from the Supreme Court of Justice
  • 2 judges elected by and from the Supreme Administrative Court
  • 4 legal and political professionals chosen by Selection Committee, approved by the Senate, and appointed by the King
  • Constitutional review
  • Disputes between branches of government
  • Upon end of 9 year term
  • Upon reaching age 70
  • Upon resignation
  • Upon removal by the Senate