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Why do some countries use unicameral legislatures with one house?
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Legislation
Former U.S. president Harry S. Truman (right) looking on as U.S. Pres. Lyndon B. Johnson signs the Medicare bill at the Harry S. Truman Library and Museum in Independence, Missouri, July 30, 1965.
A unicameral legislature consists of a single chamber or house, as opposed to a bicameral system that utilizes two. While bicameralism is often associated with federal systemsâwhere a second house is used to represent regional subdivisions or protect the interests of smaller statesâunicameralism is frequently adopted for different reasons.12
Countries often utilize unicameral legislatures for the following reasons:
- Unitary Systems: Unicameral bodies are typical in small countries and those with a unitary system of government, where there is less structural need to balance regional versus national interests through a second chamber.32
- Constitutional Trends: Following World War II, there was a growing preference for unicameral systems in many nonfederal states, leading to their adoption across various European and Latin American nations.1
- Efficiency and Simplicity: While bicameralism is theoretically justified by the principle of checks and balances to prevent hasty legislation, proponents of unicameralism often favor the streamlined process of a single chamber.1
- Size Constraints: Very small nations often find a single-chamber legislature to be the most practical and efficient structure for their governing needs.2