Unicameralism (from uni- "one" + Latin camera "chamber") is a type of legislature, which consists of one house or assembly, that legislates and votes as one. Unicameralism has become an increasingly common type of legislature, making up nearly 60% of all national legislatures and an even greater share of subnational legislatures.
Sometimes, as in New Zealand and Denmark, unicameralism comes about through the abolition of one of two bicameral 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 from the beginning.
Rationale for unicameralism and criticism
The principal advantage of a unicameral system is more efficient lawmaking, as the legislative process is simpler and there is no possibility of deadlock between two chambers. Proponents of unicameralism have also argued that it reduces costs, even if the number of legislators stays the same, since there are fewer institutions to maintain and support financially. More popular among modern-day democratic countries, unicameral, proportional legislatures are widely seen as both more democratic and effective.
Proponents of bicameral legislatures say that having two legislative chambers offers an additional restraint on the majority, though critics note that there are other ways to restrain majorities, such as through non-partisan courts and a robust constitution.
List of unicameral legislatures
Approximately half of the world's sovereign states are currently unicameral. The People's Republic of China is somewhat in-between, with a legislature and a formal advisory body. China has a Chinese People's Political Consultative Conference which meets alongside the National People's Congress, in many respects an advisory "upper house".
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 Macao, 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 regions of Italy, all of the Spanish autonomous communities, both the autonomous regions of Portugal, most of the states and union territories of India, and all of the states of Brazil and Germany. In the United Kingdom, the devolved Scottish Parliament, the Senedd Cymru, the Northern Ireland Assembly, and the London Assembly are also unicameral.
National (UN member states and observers)
Federal
Assembly of the Union of the Comoros
Bundestag of Germany
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) Congress of the Federated States of Micronesia National Assembly of Saint Kitts and Nevis Federal National Council of the United Arab Emirates National Assembly of Venezuela