Girish Mahajan (Editor)


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In government, unicameralism (Latin uni, one + camera, chamber) is the practice of having one legislative or parliamentary chamber. Thus, a unicameral parliament or unicameral legislature is a legislature which consists of one chamber or house.



Unicameral legislatures exist when there is no widely perceived need for multicameralism. Many multicameral legislatures were created to give separate voices to different sectors of society. Multiple chambers allowed for guaranteed representation of different social classes (as in the Parliament of the United Kingdom or the French States-General), ethnic or regional interests, or subunits of a federation. Where these factors are unimportant, in unitary states with limited regional autonomy, unicameralism often prevails. Sometimes, as in New Zealand and Denmark, this comes about through the abolition of one of the two chambers, or, as in Sweden, through the merger of the two chambers into a single one, while in others a second chamber has never existed.

Unicameral legislatures are also common in official Communist states such as the People's Republic of China and Cuba. Similarly, many formerly Communist states, such as Ukraine, Moldova and Serbia, have retained their unicameral legislatures, though others, such as Romania and Poland, adopted bicameral legislatures. Both the former Russian SFSR and the Union of Soviet Socialist Republics (USSR) were bicameral. The two chambers were the Soviet of Nationalities and the Soviet of the Union. The Russian Federation retained bicameralism after the dissolution of the USSR and the transition from existing socialism to capitalism.

The principal advantage of a unicameral system is more efficient lawmaking, as the legislative process is much simpler and there is no possibility of deadlock. Proponents of unicameralism have also argued that it reduces costs, even if the number of legislators stay the same, since there are fewer institutions to maintain and support it.

The main weakness of a unicameral system can be seen as the lack of restraint on the majority, particularly noticeable in parliamentary systems where the leaders of the parliamentary majority also dominate the executive. There is also the risk that important sectors of society may not be adequately represented.

List of unicameral legislatures

Approximately half of the world's sovereign states are currently unicameral, including both the most populous (the People's Republic of China) and the least populous (the Vatican City).

Many subnational entities have unicameral legislatures. These include the state of Nebraska and territories of Guam and the Virgin Islands in the United States, the Chinese Special Administrative Regions of Hong Kong and Macau, the Australian state of Queensland as well as the Northern Territory and the Australian Capital Territory, a majority of the provinces of Argentina, all of the provinces and territories in Canada, all of the German Bundesländer, all of the Regions of Italy, all of the Spanish Autonomous Communities, both the Autonomous Regions of Portugal, most of the States of India. and all of the Brazilian states.

In the United Kingdom, the devolved Scottish Parliament, National Assembly for Wales and Northern Ireland Assembly are also unicameral.


  • National Assembly of  Angola
  • National Assembly of  Armenia
  • National Assembly of  Azerbaijan
  • Jatiyo Sangshad of  Bangladesh
  • National Assembly of  Benin
  • National Assembly of  Botswana
  • Legislative Council of  Brunei
  • National Assembly of  Bulgaria
  • National Assembly of  Burkina Faso
  • National Assembly of  Cape Verde
  • National Assembly of the  Central African Republic
  • National Assembly of  Chad
  • National People's Congress of  China
  • Assembly of the Union of the  Comoros
  • Parliament of the  Cook Islands
  • Legislative Assembly of  Costa Rica
  • Sabor of  Croatia
  • Folketing of  Denmark
  • House of Assembly of  Dominica
  • National Assembly of  Djibouti
  • National Parliament of  East Timor
  • National Assembly of  Ecuador
  • House of Representatives of  Egypt
  • Legislative Assembly of  El Salvador
  • National Assembly of  Eritrea
  • Riigikogu of  Estonia
  • Parliament of  Fiji
  • Parliament of  Finland
  • National Assembly of the  Gambia
  • Parliament of  Georgia
  • Parliament of  Ghana
  • Parliament of  Greece
  • Congress of  Guatemala
  • National Assembly of  Guinea
  • National People's Assembly of  Guinea-Bissau
  • National Assembly of  Guyana
  • National Congress of  Honduras
  • National Assembly of  Hungary
  • Althing of  Iceland
  • Islamic Consultative Assembly of  Iran
  • Council of Representatives of  Iraq (provision exists for the founding of a "Council of Union", but no move to this effect has been initiated by the existing Council)
  • Knesset of  Israel
  • House of Assembly of  Kiribati
  • Assembly of  Kosovo
  • Supreme Council of  Kyrgyzstan
  • National Assembly of  Kuwait
  • National Assembly of  Laos
  • Saeima of  Latvia
  • Parliament of  Lebanon
  • House of Representatives of  Libya
  • Landtag of  Liechtenstein
  • Seimas of  Lithuania
  • Chamber of Deputies of  Luxembourg
  • Parliament of the  Macedonia
  • National Assembly of  Malawi
  • Majlis of the  Maldives
  • National Assembly of  Mali
  • Parliament of  Malta
  • Legislature of the  Marshall Islands
  • National Assembly of  Mauritius
  • Congress of  Micronesia
  • Parliament of  Moldova
  • National Council of  Monaco
  • State Great Khural of  Mongolia
  • Parliament of  Montenegro
  • Assembly of the Republic of  Mozambique
  • Parliament of  Nauru
  • Parliament of  New Zealand
  • National Assembly of  Nicaragua
  • National Assembly of  Niger
  • Assembly of  Niue
  • Supreme People's Assembly of  North Korea
  • Parliament of  Norway
  • National Assembly of  Panama
  • National Parliament of  Papua New Guinea
  • Congress of the Republic of Peru
  • Assembly of the Republic of Portugal
  • National Assembly of Saint Kitts and Nevis
  • Legislative Assembly of Samoa
  • National Assembly of São Tomé and Príncipe
  • National Assembly of Senegal
  • National Assembly of Serbia
  • National Assembly of Seychelles
  • Parliament of Sierra Leone
  • Parliament of Singapore
  • National Council of Slovakia
  • National Assembly of the Republic of Korea (South Korea)
  • Parliament of Sri Lanka
  • National Assembly of Suriname
  • Riksdag of Sweden
  • Parliament of Syria
  • Legislative Yuan of the Republic of China (Taiwan)
  • National Assembly of Tanzania
  • National Assembly of Togo
  • Legislative Assembly of Tonga
  • National Assembly of Tunisia
  • Grand National Assembly of Turkey
  • Assembly of Turkmenistan
  • Parliament of Tuvalu
  • Parliament of Uganda
  • Verkhovna Rada of Ukraine
  • Pontifical Commission for Vatican City State
  • National Assembly of Venezuela
  • National Assembly of Vietnam
  • Assembly of Representatives of Yemen
  • National Assembly of Zambia
  • Territorial

  • House of Assembly of the British Virgin Islands
  • Legislative Assembly of the Cayman Islands
  • Parliament of Greenland
  • The Løgting of the Faroe Islands
  • Parliament of Gibraltar
  • Legislature of Guam
  • Legislative Council of Hong Kong (divided into two groups for private members' bills since 1998)
  • Legislative Assembly of Macau
  • Legislature of the U.S. Virgin Islands
  • Federations

  • All legislatures and legislative councils of the regions and communities of Belgium
  • All legislative assemblies of the provinces of Canada
  • All Landtage of the states of Germany
  • All legislative assemblies of the states of Malaysia
  • The legislature of the state of Nebraska, US
  • Council of Washington, D.C. (United States)
  • Parliament of Queensland and the legislative assemblies of the territories of Australia (but not the states)
  • Provincial legislatures of the Provinces of South Africa
  • Narodna skupština of Republika Srpska
  • All legislative assemblies in all states of Brazil
  • All legislatures in all states of Mexico
  • 15 of the Provinces of Argentina – Chaco, Chubut, Córdoba, Formosa, Jujuy, La Pampa, La Rioja, Misiones, Neuquén, Río Negro, San Juan, Santa Cruz, Santiago del Estero, Tierra del Fuego, Tucumán and the autonomous city of Buenos Aires.
  • 22 States and 2 Union Territories in India – Arunachal Pradesh, Assam, Chhattisgarh, Goa, Gujarat, Haryana, Himachal Pradesh, Jharkhand, Kerala, Madhya Pradesh, Manipur, Meghalaya, Mizoram, Nagaland, Odisha, Punjab, Rajasthan, Sikkim, Tamil Nadu, Tripura, Uttarakhand, West Bengal and Delhi, Puducherry
  • All Provinces in Pakistan – Baluchistan, Khyber Pakhtunkhwa, Sindh and Punjab plus legislature of Gilgit Baltistan
  • Devolved governments

  • Kurdish Parliament
  • Northern Ireland Assembly
  • Scottish Parliament
  • National Assembly for Wales
  • Parliaments of the autonomous communities of Spain
  • Other

  • Local People's Congresses of all levels of provinces, regions and municipalities of the People's Republic of China
  • State House of Assembly All States in Nigeria
  • National

  • The First Protectorate Parliament and Second Protectorate Parliament of the Kingdom of England, regulated by the Instrument of Government (dissolved)
  • Parliament of the Kingdom of Scotland until 1707 (dissolved)
  • Congress of the Confederation was unicameral before being replaced in 1789 by the current, bicameral United States Congress.
  • Congress of Deputies of Second Spanish Republic was unicameral between 1931 and 1936. Dissolved at the end of Spanish Civil War; the actual Spanish Parliament (1978-now) is bicameral.
  • Supreme Assembly of Uzbekistan was unicameral before being replaced in 2005 by the current, bicameral Supreme Assembly.
  • National Assembly of Cameroon was unicameral before being replaced in 2013 by the current, bicameral Parliament of Cameroon.
  • Chamber of People's Representative of Equatorial Guinea was unicameral before being replaced in 2013 by the current, bicameral Parliament of Equatorial Guinea.
  • National Assembly of Kenya was the country's unicameral legislature before becoming the lower house of the bicameral Parliament of Kenya in 2013.
  • National Assembly of Ivory Coast was the country's unicameral legislature before becoming the lower house of the bicameral Parliament of Ivory Coast in 2016.
  • Subnational

  • General Assembly of Georgia until 1789
  • General Assembly of Pennsylvania until 1790
  • General Assembly of Vermont until 1836
  • Unicameralism within the subdivisions of the United States

    Within U.S. states, Nebraska is currently the only state with a unicameral legislature; after a statewide vote, it changed from bicameral to unicameral in 1937. Nebraska's state legislature is also unique in the sense that it is the only state legislature that is entirely nonpartisan.

    Local government legislatures of counties, cities, or other political subdivisions within states are usually unicameral and have limited lawmaking powers compared to their state and federal counterparts.

    In 1999, Governor Jesse Ventura proposed converting the Minnesota Legislature into a single unicameral chamber. Although debated, the idea was never adopted.

    In a non-binding referendum held on July 10, 2004, voters in the U.S. territory of Puerto Rico approved changing its Legislative Assembly to a unicameral body by 456,267 votes in favor (83.7%) versus 88,720 against (16.3%). If both the territory's House of Representatives and Senate had approved by a 23 vote the specific amendments to the Puerto Rico Constitution that are required for the change to a unicameral legislature, another referendum would have been held in the territory to approve such amendments. If those constitutional changes had been approved, Puerto Rico could have switched to a unicameral legislature as early as 2015.

    On June 9, 2009, the Maine House of Representatives voted to form a unicameral legislature, but the measure did not pass the Senate.

    Because of legislative gridlock in 2009, former Congressman Rick Lazio, a prospective candidate for governor, has proposed that New York adopt unicameralism.

    The United States as a whole was subject to a unicameral Congress during the years 1781–1788, when the Articles of Confederation were in effect.

    Unicameralism in the Philippines

    Though the current Congress of the Philippines is bicameral, the country experienced unicameralism in 1898 and 1899 during the First Philippine Republic, from 1935 to 1941 during the Commonwealth Era and from 1943 to 1944 during the Japanese occupation. Under the 1973 Constitution, the legislative body was called Batasang Pambansa, which functioned also a unicameral legislature within a semi-presidential system form of government until 1986.

    The ongoing process of amending or revising the current Constitution and form of government is popularly known as Charter Change. A shift to a unicameral parliament was included in the proposals of the constitutional commission created by former President Gloria Macapagal-Arroyo. Unlike in the United States, senators in the Senate of the Philippines are elected not per district and state but nationally; the Philippines is a unitary state. The Philippine government's decision-making process, relative to the United States, is more rigid, highly centralised, much slower and susceptible to political gridlock. As a result, the trend for unicameralism as well as other political system reforms are more contentious in the Philippines.

    While Congress is bicameral, all local legislatures are unicameral: the ARMM Regional Legislative Assembly, the Sangguniang Panlalawigan (Provincial Boards), Sangguniang Panlungsod (City Councils), Sangguniang Bayan (Municipal Councils), Sangguniang Barangay (Barangay Councils) and the Sangguniang Kabataan (Youth Councils).


    Unicameralism Wikipedia