Unicameral system

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.

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