Source: https://tlc.texas.gov/redist/history/overview_house.html
Timestamp: 2019-04-26 16:06:10+00:00

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The 1845 Texas Constitution apportioned the state's counties to 13 single-member districts and 23 multi-member districts that elected 53 representatives. All 66 members served two-year terms. Subsequent apportionments, required at the meeting of each legislature until 1850 and every eight years thereafter, were based on enumerations of "qualified electors." The 1845 constitution allowed the house membership to vary between 45 and 90 representatives.
In 1848, the 2nd Legislature, Regular Session, began apportioning certain counties to flotorial districts in addition to single-member and multi-member districts. Flotorial districts were large multi-county districts that shared overlapping common territory with smaller districts.
The legislature enacted new house districts regularly until 1860. Membership of the house expanded from 49 to 90 representatives.
During Reconstruction, state house districts were coextensive with state senate districts. The 1869 Texas Constitution fixed the number of representatives at 90. Each of the 30 senate districts was apportioned two to four representatives. The legislature was required to conduct reapportionments at the first meeting of the legislature following the publication of each federal census.
Current redistricting practice is based on the 1876 Texas Constitution. Membership of the house was initially set at 93. Future apportionments could expand the number of representatives to 150 based on a population ratio. The legislature returned to the practice of using a combination of single-member, multi-member, and flotorial districts. This method of apportionment continued until 1968.
New house districts were enacted by the legislature, following the publication of each federal decennial census through 1921.
The legislature did not pass state house reapportionment bills following the census in 1930 or 1940. An amendment to the constitution, adopted by voters in 1948, created the Legislative Redistricting Board, with the power to reapportion state house and senate districts if the regular session of the legislature failed to act following the federal census. Subsequently, the legislature enacted regular reapportionments of the house in 1951 and 1961.
In 1964, the U.S. Supreme Court in Reynolds v. Sims ruled that the population of state legislative districts should be relatively equal. That same year, in Kilgarlin v. Martin, a federal court held the Texas constitutional provision that restricted the number of representatives apportioned to populous counties unconstitutional. In 1965, the 59th Legislature, Regular Session, enacted new state house districts.
In 1967, the U.S. Supreme Court in Kilgarlin v. Hill affirmed a federal district court ruling that invalidated the flotorial districts enacted by the 59th Legislature because they violated the equal population requirement of Reynolds v. Sims. The 60th Legislature enacted a new state house apportionment in 1967 that eliminated the flotorial districts, but retained the multi-member districts. In 1969, the 61st Legislature made changes to certain districts enacted in 1967.
In 1971, the 62nd Legislature, Regular Session, passed a house apportionment bill. The act was found unconstitutional by the Texas Supreme Court in Smith v. Craddick because the plan unnecessarily divided counties into more than one district. The Texas Supreme Court, in Mauzy v. Legislative Redistricting Board, also ordered the Legislative Redistricting Board to reapportion the state house. The board ordered new house districts in October 1971. A federal district court, in Graves v. Barnes, later modified the districts by creating single-member districts for Bexar and Dallas Counties.
The 62nd Legislature, 4th Called Session, 1972, and the 63rd Legislature, Regular Session, 1973, made changes to certain house districts.
In 1974, in Graves v. Barnes, a federal district court invalidated the remaining multi-member house districts. In 1975, the 64th Legislature, Regular Session, enacted a new house apportionment plan that for the first time in Texas history was composed solely of single-member districts. The plan remained in effect through the 1980 elections.
See also: Legislative Reference Library chart listing Texas legislative and congressional redistricting bills: 1880–present.
The Texas Legislative Council, a nonpartisan legislative service agency, provides technical and legal support to the Texas legislature for redistricting.

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