The map is of the bicameral and unicameral nations. In the US, Nebraska is the only state with a unicameral legislature. In government, unicameralism 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.
Three additional attempts to achieve a one-house legislature proved unsuccessful, including a 1923 initiative petition campaign that ultimately failed to garner sufficient signatures to place the measure on the ballot.15 Nevertheless, by the early 1930s, the concept was beginning to attract more attention both nationally and within the state. This was due in large part to the notoriety of its most outspoken advocate, U.S. Senator George W. Norris of Nebraska.16
As early as 1913, the Progressive Movement in Nebraska had begun to lobby for government reform with one of the principle goals of implementing a one-house legislative system.11 In 1917, a resolution was successfully passed in the Nebraska Legislature to call a constitutional convention in order to consider revisions to the state's charter document, including the potential for a one-house legislature.12 The voters approved the resolution at the 1918 general election by a vote of 121,830 to 44,491 with the wide margin perhaps indicating a popular belief that changes were indeed necessary.13
Alaska gave the concept consideration as its citizens prepared for entry into the union. Jonathan Ross (2010) traces the considerations made by delegates to the Alaska Constitutional Convention in 1955.
Vermont used a unicameral legislative structure from 1777 until 1835.
Vermont had “borrowed” the structure from Pennsylvania. Georgia was the other state
to start out with a unicameral structure (Minnesota Legislative Reference Library 2010)
Today unicameralism flourishes in Nebraska and in numerous city governments throughout the United States. Nebraska's voters authorized a single chamber legislature in 1934,53 and the first session was held in 1937
In France, unicameralism was always advocated by republican groups, and they have sometimes succeeded in taking away important powers from the tipper chamber when the constitution has been redrawn.
Thus, a unicameral parliament or unicameral legislature is a legislature which consists of one chamber or house. Some countries with unicameral legislatures are often small and homogeneous unitary states and consider an upper house or second chamber unnecessary.
Unicameral legislatures are also common in 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 Russia and Poland, adopted bicameral legislatures after the fall of Communism.
Another unique aspect of Nebraska's legislature is its nonpartisanship. Before becoming a unicameral, the Nebraska Legislature was a partisan body. The change to nonpartisanship was included in the successful 1934 unicameral amendment.
Implementation of the unicameral legislature in 1937 cut government costs for obvious reasons. Legislative membership went from 133 in the bicameral to 43 in the new single house - nearly a 70 percent reduction.
The word "cameral" comes from the Latin camera and the Greek kameral, both meaning "chamber." Therefore, a unicameral legislature consists of only one chamber or legislative house.