Copies of this publication have been distributed in compliance with the State Depository Law and are available for public use through the Texas State Publications Depository Program at the Texas State Library and other state depository libraries. An online version of this publication can be found at http://www.tlc.state.tx.us/research/pubs.htm.

Introduction

Executive Summary

• Basic Legal Requirements
• Senate Districts
• House Districts
• Congressional Districts
• State Board of Education Districts

• Public Hearings (Presession Preparation)
• Redistricting Bills (Regular Session Activities)
• Legislative Redistricting Board
• Voting Rights Act Submissions
• Judicial Review
• 2002 Elections
• 2001 Redistricting Timetable

• Data
• Redistricting Computer Systems
• Maps and Reports

• 1991 Redistricting History
• Voting Rights Lawsuits
• Shaw v. Reno-Based Lawsuits
• 1990s Redistricting Chronology

The Guide to 2001 Redistricting was prepared to provide members of the legislature and other interested persons with an introduction to the issues and constraints that will affect the redistricting process in Texas following the 2000 decennial census and to the types of services that will be provided by the Texas Legislative Council to support the state's redistricting effort. It is the second of a series of publications planned by the council that will cover legal issues, demographic trends, policies, procedures, and data relating to redistricting.

This guide explains the redistricting process in Texas, briefly outlines requirements of a redistricting plan, and provides an account of the history of Texas redistricting in the 1990s. It discusses the data that legislators will have in 2001 and the computer support that will be available to facilitate the drawing and analysis of districts. It also includes a glossary of redistricting terms.

For more information concerning redistricting, contact the Texas Legislative Council at (512) 463-1143.

The Texas Legislature is required to redistrict house and senate districts in the first regular session immediately following the release of the United States decennial census and also to redistrict congressional and State Board of Education districts before the 2002 elections. Redistricting cannot start until the block-level total and voting age population counts by race and ethnicity are provided by the Census Bureau on or before April 1, 2001. If the legislature does not pass new house or senate district boundaries by the end of the session, May 28, 2001, or the governor vetoes one of the acts, the state constitution requires the five-member Legislative Redistricting Board to meet and enact a new redistricting plan. If the legislature fails to redraw congressional or State Board of Education districts during the regular session, or the governor vetoes one of the acts, the issue may be taken up in a special legislative session. To accomplish its task in the very limited time available, the legislature must have access to a large amount of information and the ability to analyze it quickly and efficiently.

In 2001, Texas legislators will have more information and better computer support to facilitate the redistricting task than ever before. In 1991, legislators drew plans using a graphical redistricting modeling application, the RedAppl system, which was available on only eight computer workstations in council offices. The 2001 RedAppl system will be an enhanced version of the 1991 RedAppl system and will run on a PC in each member's Capitol office. This system has the same functionality as its predecessor, but it also has some new features and is much faster and more user-friendly. In addition, clients will be able to request and view some maps and reports online and to print them in their offices. Online viewing of current districts and proposed public plans will also be available to members and the public using the council's Internet application called RedViewer. Another computer tool that may be available to aid members in the redistricting process is TARGET, which can generate a redistricting plan from a set of goals defined by the user. This program cannot produce an optimum redistricting plan, but rather is a tool to quickly generate a starting point, explore possibilities, or search for solutions to problems.

Even with the new, improved computer systems, redistricting is a complex and challenging political process, as is evident by the number of lawsuits in Texas alone during the 1990s. The council plans to produce publications on legal requirements and the data used in redistricting to provide additional background for persons who will be involved in redistricting in the 2000s.

The Texas Constitution requires the legislature to redistrict house and senate seats during its first regular session following publication of each United States decennial census (Section 28, Article III). The federal constitution calls for reapportionment of congressional seats according to population from a decennial census (Section 2, Article I). The population disparity among State Board of Education (SBOE) districts after the 2000 census will also require the redrawing of those districts for compliance with the one-person, one-vote requirement. As a result, the Texas Legislature will be involved in redistricting state senate, state house, U.S. House of Representatives, and SBOE district boundaries during the 77th Regular Session.

Redistricting is the revision or replacement of existing districts, resulting in new districts with different geographical boundaries. The basic purpose of decennial redistricting is to equalize population in state and congressional districts after publication of the United States census indicates an increase or decrease in or shift of population.

Reapportionment is the division of a set number of districts among established units of government. For example, the 435 congressional seats are reapportioned among the 50 states after each decennial census according to a complex formula established by the congress (the method of equal proportions, Huckabee, 1988). The boundaries of the congressional districts are then redrawn by state legislatures in accordance with state and federal law and guidelines developed by the courts.

Two primary requirements govern all redistricting decisions in the state. First, districts of a given type (senate, house, congressional, SBOE) must have equal or nearly equal populations, and second, districts must be drawn in a manner that does not have the purpose and will not have the effect of denying or abridging the right to vote on the basis of race or language group. These requirements are based in certain guarantees of the Fourteenth Amendment to the U.S. Constitution (the Equal Protection Clause), the Fifteenth Amendment (prohibiting voting discrimination because of race), the federal Voting Rights Act of 1965, and, for congressional districts, Section 2, Article I, of the U.S. Constitution. As U.S. Supreme Court Justice William O. Douglas wrote in 1963, "The conception of political equality from the Declaration of Independence, to Lincoln's Gettysburg Address, to the Fifteenth, Seventeenth, and Nineteenth Amendments could mean only one thing--one person, one vote." (Gray v. Sanders, 372 U.S. 368, 83 S. Ct. 801)

The first question that must be answered about redistricting is exactly how equal the populations of districts must be. A Texas case that reached the U.S. Supreme Court in the 1970s (White v. Regester, 412 U.S. 755, 93 S. Ct. 2332 (1973)) set a standard for the maximum acceptable population deviation for state legislative districts at less than 10 percent of the ideal district size. "Ideal district population" is the population a district would have if all districts in a plan have equal populations, and it is determined by dividing the total state population by the number of districts in the plan. This standard is still generally valid, although exceptions have been allowed if based on consistent application of rational state policy.

The federal constitutional and statutory provisions on redistricting, the differing provisions of the Texas Constitution relating to legislative districts, and numerous federal and state court cases on the issue result in somewhat different requirements for different types of districts. The following sections briefly describe the basic requirements for drawing the districts for which the Texas Legislature is primarily responsible.

The total population of Texas according to the 1990 census was 16,986,510; the ideal district size for the 31 senate districts was 547,952, and district sizes varied between 512,389 and 567,088. The deviation range in the senate plan now in effect is from -6.49 percent to +3.49 percent, for an overall deviation of 9.98 percent. According to the most recent projections, the total state population for 2000 is projected to be approximately 20.45 million; if that projection is accurate, the ideal senate district size in 2001 will be approximately 660,000.

Section 25, Article III, of the Texas Constitution requires senate districts to be composed of contiguous territory and to be single-member districts. That section also states that a county is entitled to no more than one senator, a provision that cannot be followed if its application violates the equal population requirement of the Fourteenth Amendment to the U.S. Constitution. Section 25 also requires senate districts to be drawn according to the number of qualified electors, a provision that has never been followed because the detailed population data necessary for redistricting has never been available for "qualified electors" and because it has been feared that reliance on qualified electors rather than total population might result in impermissible population variation or in dilution of minority voting rights.

Section 28, Article III, of the Texas Constitution requires the legislature to redistrict state senate districts during the first regular session following publication of the decennial census. If the legislature fails to do so, the redistricting task falls to the Legislative Redistricting Board (LRB). In Mauzy v. LRB, 471 S.W.2d 570 (Tex., 1971), the Texas Supreme Court interpreted the LRB's authority to arise not only when the legislature literally fails to act, but also when legislative redistricting plans are found invalid. As a result, if the legislature's plan is vetoed by the governor, or overturned by a court challenge within the 90-day period in which the LRB is given redistricting authority, redistricting becomes the responsibility of the LRB.

In 1990, the ideal house district size was 113,243. The actual size of the house districts under the current house plan varies between 107,265 and 118,575. The deviation range is from -5.28 percent to +4.71 percent, for an overall deviation of 9.99 percent. Assuming a 2000 state total population of approximately 20.45 million, house districts will have to increase to an ideal population size of approximately 136,400.

Section 26, Article III, of the Texas Constitution, requires that house districts be apportioned among the counties according to the federal census population and the following rules:

  (1) a county with sufficient population for exactly one district must be formed into a single district;

  (2) a county with a population smaller than the population needed for a whole district must be kept whole and combined with other contiguous counties to form a district;

  (3) a county that can hold a multiple of whole districts must be apportioned those districts, with no district extending into another county; and

  (4) each county with a population sufficient for one or more whole districts plus a fraction of another district must be divided into that many whole districts, with the excess population added to other adjacent counties to form an additional district.

In practice, it is sometimes impossible to draw a statewide plan that completely satisfies these rules. The Texas courts have allowed a plan to violate the rules only to the extent necessary to draw a complete plan.

Section 28, Article III, of the state constitution requires the LRB to undertake house redistricting within 90 days if the legislature fails to enact an acceptable house plan during the first regular session following publication of the decennial census.

The number of congressional districts apportioned to each state is determined by a mathematical formula set by federal law. Unless a state's constitution provides otherwise, each legislature has the authority to draw its state's congressional district boundaries. No Texas constitutional or statutory provisions address congressional redistricting, but in recent decades the process has usually occurred during the legislative session that is meeting when the decennial census is published and the legislature is also redrawing state house and senate districts. Unlike legislative redistricting, however, congressional redistricting does not come within the authority of the LRB if the legislature fails to enact a valid plan during the regular session. The issue may be taken up in a subsequent special session of the legislature.

The law allows less population deviation for congressional districts than for legislative districts. In congressional districts, each deviation from the ideal district size must be justified on the basis of a rational state policy or be found to be unavoidable despite a good faith effort to draw districts with equal population. (Karcher v. Daggett, 462 U.S. 725, 103 S. Ct. 2653 (1983))

Following the 1990 census, the state gained three congressional seats to bring the number of Texas districts to 30. The ideal district population was 566,217; in the plan adopted by the legislature in 1991, all districts had exactly equal populations.

The number of congressional districts apportioned to Texas in 2001 will be determined not only by the population of the state, but also by the number of people counted in other states. If the state has approximately 20.45 million people in 2000 and if two new congressional seats are gained as is generally predicted, the ideal district population for each of the 32 districts will be approximately 639,000.

Before 1984, members of the SBOE were elected from districts that matched congressional districts, and the legislature did not specifically consider SBOE redistricting. The education reform measure that was passed in 1984 reduced the number of SBOE members from 27 to 15. That legislation (Chapter 28, Acts of the 68th Legislature, 2nd Called Session, 1984) also established district boundaries and provided that the board undergo decennial redistricting.

The 1990 census populations of the current SBOE districts, adopted by the legislature in 1991, range from 1,087,970 to 1,178,804, with an overall deviation of 8.02 percent from the ideal district size of 1,132,434.

In 2001, the ideal SBOE district population size is expected to be approximately 1,363,500.

Public Hearings (Presession Preparation)

Under federal regulations for the administration of the Voting Rights Act, a state seeking preclearance from the U.S. Department of Justice is required to submit to the department materials that document the legislature's consideration of public sentiment in its redistricting decisions and that show that recognized racial and language minority groups had a reasonable opportunity to participate in the process. In order to address these considerations and to gather information that will aid the legislature in making redistricting decisions, legislative committees will hold public hearings throughout the state in the months leading up to the 2001 redistricting session. While no official census population data will be available until spring of 2001, the hearings will provide an opportunity for citizens to present relevant testimony concerning local preferences, communities of interest, local voting patterns, and other issues that the legislature may consider when redrawing district lines.

Redistricting Bills (Regular Session Activities)

The Census Bureau will deliver state populations to the president by December 31, 2000, at which time the number of congressional seats for each state will be computed. The detailed population data necessary for redistricting must be delivered to the states by April 1, 2001. This gives the Texas Legislature only 57 days during the regular session to draw and adopt legislative district boundaries. After the legislature receives the census data, it will take several days to load the data onto the council computer system, verify the integrity of the data, and ensure that the system is functioning correctly. Current house and senate rules place further limitations on the time available to pass redistricting bills.

All legislators will have access to the redistricting application, RedAppl 2001, in their Capitol offices to use in preparing district proposals. Other services, such as production of population analyses, maps, and bill drafts, will also be available.

Redistricting bills follow the same path through the legislature as other legislation. Congressional and SBOE district bills may be introduced in either or both houses; senate and house redistricting bills traditionally originate only in their respective houses. Following final adoption by both houses, each redistricting bill is presented to the governor for approval. The governor may sign the bill into law, allow it to take effect without a signature, or veto it. If the legislature's house or senate redistricting bill is vetoed, the LRB is required to meet. If the congressional or SBOE plan is vetoed, the governor may call a special session to consider the matter.

Enacted redistricting plans or those adopted by the LRB are filed with the Texas secretary of state and are subject to federal preclearance under the Voting Rights Act. The plans adopted in 2001 will become effective for the 2002 primary and general elections, pending preclearance and judicial review.

The Legislative Redistricting Board, composed of the lieutenant governor, speaker of the house, attorney general, comptroller, and land commissioner, was created by constitutional amendment in 1951, at least in part to provide legislators with an incentive to redistrict after each federal decennial census. If the legislature fails to redistrict house and senate districts during the first regular session following release of the decennial census, Section 28, Article III, of the Texas Constitution requires the board to meet within 90 days of the end of that regular session and to adopt its plans within 60 days of convening. If the LRB meets in 2001, members of the board will be provided access to the redistricting services provided by the legislative council.

For states covered by Section 5 of the federal Voting Rights Act, including Texas, changes in laws affecting elections must be evaluated to determine that they do not have the purpose and will not have the effect of denying or abridging the right to vote on the basis of race or language group. Because of this requirement, redistricting plans passed by the Texas Legislature or the LRB must be submitted to the U.S. Department of Justice or the federal District Court for the District of Columbia for preclearance. The state may not implement a new redistricting plan until the plan has been precleared under Section 5 of the Act.

If a plan is submitted to the justice department, the department has 60 days to review the plan; if department officials request additional information, another 60-day review period begins on the date the supplementary material is received. If the justice department objects to all or parts of any plan, either the legislature must make revisions, which would again be subject to preclearance, or the plan may be submitted to the federal District Court for the District of Columbia for preclearance.

A suit against an adopted redistricting plan may be brought at any time under the federal or state constitution or federal law. A suit alleging that a plan does not meet Texas constitutional requirements ordinarily is filed in state court. A suit alleging that a plan violates federal law is ordinarily filed in federal district court.

Before the 2002 elections, counties that are split by district boundaries must change their voting precinct boundaries to conform with the new district lines. These county precinct boundary changes are also subject to preclearance under the Voting Rights Act.

The January 2 filing deadline for the 2002 primary elections allows only seven months from the end of the regular legislative session in 2001 for the governor to act on the legislation, for the LRB to meet if necessary, for any special session called to consider redistricting if necessary, for obtaining preclearance under Section 5 of the Voting Rights Act, for court action, and for counties to make necessary changes in voting precincts. In addition, the state constitution requires a candidate for state legislative office to have resided for at least one year in the district the candidate seeks to represent.

This section describes the population and election data and the redistricting computer services that will be available to help members draw and evaluate redistricting proposals.

Because the impetus for redistricting is the federal constitutional requirement that districts of a given type have equal or nearly equal population (one person, one vote), redistricting plans must include information about the total population of each district. To satisfy other legal requirements, plans must include information about the race/ethnicity of the total and the voting age populations of the districts. In addition, the Voting Rights Act and court cases establish the need for election data for analyzing minority participation in elections and partisan voting patterns in existing and proposed districts. Finally, since districts are defined in terms of geographic territory, geographic features such as census units (tracts, block groups, and blocks) and political units (counties, cities, voting precincts) that are correlated to the demographic and political data are required for the task of redistricting.

Much of the base data needed for redistricting will be provided by the Census Bureau, including the TIGER geographic database and block level population counts by racial and ethnic category. A statewide election database, compiled by legislative council staff since the mid-1980s, will provide precinct boundaries, the results of primary and general elections, and voter registration information by precinct for all counties.

Redistricting information provided by the legislative council will consist primarily of maps and data on total and voting age population by race/ethnicity and election and voter information. Population data is the foundation of a redistricting plan; it is reported by census geography, and redistricting plans are drawn on census geography. Election data is necessary to satisfy Voting Rights Act requirements for redistricting; it is reported by county voting precinct, but it may be estimated in the process of matching it to census geography.

Because of differences between voting precinct geography and census geography, the legislative council has overlaid every voting precinct in the state on census block maps. Where precinct lines do not follow census block boundaries (the smallest unit for which population data is reported), the voting precinct boundaries have been approximated to the closest block boundary. These approximated precincts are called voting tabulation districts (VTDs). In many cases, they will match precincts exactly. In most cases where the two do not match, the differences will be minor and will involve no population, and in limited cases, the changes made by the approximations are substantial, and the reliability of election data reported for those VTDs is diminished accordingly. However, because districts cover large areas and incorporate many precincts, and only approximated VTDs that serve as a district boundary are of concern, the approximations do not present a significant problem.

The RedAppl 2001 graphical district modeling system is being developed to run as a PC application and will be available on one PC in each member's Capitol office. The council will also provide appointments with council operators for those who do not want to learn the application. The new RedAppl will be similar to its predecessor in its capabilities and functionality, but with added features. The new application will be much faster and more user-friendly, so that it can be operated independently by the client. The council will provide classes to teach clients in the legislative community to use RedAppl 2001 and will have staff available for technical assistance regarding the application.

In addition to RedAppl, a computerized tool called TARGET, which would quickly generate a redistricting plan based on certain variables selected by the user, may be available to members. TARGET would run as a separate application, but TARGET plans could be imported into RedAppl 2001, and RedAppl 2001 plans could be imported into TARGET. To use TARGET, a client would have to work with trained council staff to construct a quantitative expression of a set of goals, which would then be transferred to the client's PC to run. TARGET could not produce an optimum redistricting plan, but rather would be a tool to more quickly generate a starting point, explore possibilities, or search for solutions to problems.

Maps and reports summarizing data are critical to the redistricting process. In 2001, clients will be able to request from a local PC selected reports and simple black and white maps for viewing online or printing locally, while the more complicated reports and color maps will be processed through the council. The equipment needed to produce large color maps necessitates centralized production of those maps. Similarly, the programs that build redistricting reports are complex, and many require lengthy processing or printing times, necessitating use of the council mainframe or system printer.

Additional online viewing of maps and reports will be available through a council-developed Internet application, RedViewer. RedViewer will allow anyone with Internet access to view current or proposed public redistricting plans online. Users of the system will be able to select specific counties or districts and be able to choose some of the information displayed on the map, such as precincts or major roads.

On February 5, 1991, the P.L. 94-171 computer tapes of 1990 census counts were delivered to the council. A nongraphic district modeling system, PAS, was available for redistricting on February 13. After database building and verification, the RedAppl system was available to clients on March 22.

The legislature passed bills redrawing house and senate district boundaries in the 1991 regular session. An August special session (72nd Legislature, 2nd Called Session) resulted in the passage of a congressional district bill and an SBOE district bill.

During 1991, suits were filed in state district court and federal district court asserting voting rights complaints against the adopted house and senate redistricting plans and against the as yet unmodified SBOE and congressional plans. After two special sessions (August 1991 and January 1992) and numerous legal actions, the 1992 house and senate elections were ultimately conducted under court-ordered plans that changed 37 of the 150 house districts and 30 of the 31 senate districts that had been adopted by the legislature during the regular session. The 1992 congressional and SBOE elections were held under the plans passed by the legislature in the August 1991 special session.

The 1994 elections were held under districts enacted by the legislature in the January 1992 special session. House districts were slightly modified from the 1992 districts ordered by the court in December 1991. The senate districts were significantly different from those used for the 1992 election.

On January 26, 1994, suit was filed in federal court in Houston challenging the Texas congressional districts as unconstitutionally racially gerrymandered under the framework of the recent U.S. Supreme Court cases Shaw v. Reno and Hays v. Louisiana. In the summer of 1994, the court held three of the districts unconstitutional. The state appealed the case to the U.S. Supreme Court and proceeded to conduct the 1996 primaries under the state's plan. In June 1996, the supreme court upheld the district court's decision. The district court voided the results of the 1996 primary elections in 13 of the state's 30 congressional districts and ordered a special election to be held in those 13 districts on general election day using an interim plan drawn by the court. The district court gave the legislature until June 30, 1997, to enact a permanent plan, but the 75th Legislature did not adopt a plan within that time. On September 15, 1997, the court dismissed all pending motions and ordered the court-drawn plan into effect for the 1998 congressional elections.

On January 25, 1995, Thomas v. Bush was filed in federal court challenging 13 senate districts and 54 house districts as unconstitutionally racially gerrymandered. On September 15, 1995, the court ordered an agreed settlement under which eight senate districts and 36 house districts were changed, the staggered senate terms drawn by lot in January 1994 were allowed to remain in effect, and the one-year prior residency requirement was waived for the changed districts so that a candidate could run either in the same numbered district in which the candidate resided under the prior plan or in the new district in which the candidate resided.

During the 1997 regular session, the Texas Legislature passed S.B. 715, which enacted without change the senate districts approved in the 1995 Thomas v. Bush settlement. That plan was subsequently used for the 1998 elections. Also enacted during the 1997 regular session were two bills affecting state house districts. House Bill 6 enacted the state house districts approved in the 1995 Thomas v. Bush settlement with additional minor changes to six districts, and H.B. 2254 made minor changes to eight other house districts. The U.S. Department of Justice precleared the changes, and the plan was used for the 1998 elections.

Court actions in the summer of 1997 effectively brought an end to required action by the legislature on 1991 redistricting.

Census block: The smallest unit of census geography for which population data are reported. Census blocks are designated by the Census Bureau and are generally bounded by physical features such as roads, creeks, or railroads, though in some cases they may be bounded by nonvisible features such as city limits.

Census block group: A cluster of census blocks within a census tract designated by the Census Bureau as a subdivision of that census tract.

Census Day: April 1, 2000. The date for which census data will be collected.

Census tract: A unit of census geography defined by the Census Bureau for the purpose of presenting decennial census data. Census tracts are made up of block groups. Their boundaries generally follow visible features, though in some circumstances their boundaries may follow governmental unit boundaries or other nonvisible features. In general, census tracts must contain between 1,500 and 8,000 inhabitants.

Community of interest: A grouping of people, such as in a city or a neighborhood, that has common political, social, or economic interests.

Compactness: The degree to which the territory assigned to a district is close together. There are several mathematical ways to measure the elements of compactness.

Contiguity: Adjacency. For redistricting purposes, a district is considered to be contiguous if all parts of the district touch one another at more than a point, so that the entire district is within a continuous boundary. Legal standards governing redistricting for various governmental bodies often require all of the territory in each district to be contiguous.

County election precincts: Geographic units established by county commissioners courts for the purpose of election administration. The voters in an election precinct usually vote at a single polling place, so the votes cast in the precinct may be counted separately from other precincts.

Deviation: The amount by which a district's population differs from the ideal district population for the particular plan type.

Differential undercount: The extent to which one group of persons is more likely to be undercounted in the decennial census than other groups. For example, in the 1990 census, though almost 100 percent of white persons where counted, approximately 5 percent of black and Hispanic persons were not counted. See "Undercount."

Equal Protection Clause: See "Fourteenth Amendment to the U.S. Constitution."

Fourteenth Amendment to the U.S. Constitution: The U.S. Constitution provision that includes the Equal Protection Clause, which prohibits the states from denying persons equal protection of the law. The Equal Protection Clause is the primary basis of the one-person, one-vote principle.

Fifteenth Amendment to the U.S. Constitution: The U.S. Constitution provision that the right to vote may not be denied or abridged on account of race.

Fragmentation: The division of a geographically concentrated group, such as a racial or political group, among different districts for the purpose of minimizing the group's voting strength.

Geographic Information System (GIS): A graphics-based computer system that relates geographic features (such as census tracts, roads, or counties) to data about those features (such as population, race, or income).

Gerrymander: A district or set of districts with unusual boundaries that is drawn in that way to favor one or more interest groups over others.

Ideal district population: A measure calculated by dividing the total population of the state or other jurisdiction being redistricted by the number of districts in the type of redistricting plan being considered. For example, in 1991, the ideal district population for Texas senate districts was 547,952, which is the 1990 state population (16,986,510) divided by 31 senate districts.

Legislative Redistricting Board: The body responsible for adopting legislative redistricting plans if the legislature fails to enact such plans during the regular session following the publication of the decennial census. The board consists of the lieutenant governor, speaker of the house, attorney general, comptroller, and land commissioner. See Section 28, Article III, of the Texas Constitution.

Method of equal proportions: The mathematical formula used as provided by federal statute to reapportion congressional seats among the states after each decennial census.

Minority vote dilution: The creation of districts that either (1) divide members of a racial or ethnic minority group among several districts, artificially reducing the group's opportunity to influence elections (see "Fragmentation") or (2) place extraordinarily high percentages of members of a racial or ethnic minority group in one or more districts, so that minority voting strength is artificially limited to those districts and is minimized in neighboring districts (see "Packing").

One person, one vote: The principle that each person's vote should count equally to every other person's vote, which is effected by the allocation of the same or substantially the same population to each district of a particular type, such as a congressional district. The courts derive the one-person, one-vote standard primarily from the Equal Protection Clause of the Fourteenth Amendment to the U.S. Constitution. For congressional districts, the one-person, one-vote requirement also derives from Section 2, Article I, and from Section 2 of the 14th Amendment to the U.S. Constitution.

P.L. (Public Law) 94-171: The federal statute that requires the Census Bureau to provide, by April 1 of each year following a decennial census, the population and race data necessary for redistricting.

Packing: Creating a district with a very high concentration of a particular group of voters, such as a racial or political group, tending to result in the election of the group's candidate of choice in any election in that district and the dilution of the group's voting strength in neighboring districts.

Population estimates: An approximation of the population of a geographic unit at a point in the past or present for which an actual population count is not available.

Population projections: An approximation of the population of a geographic unit at a point in the future based on specific assumptions regarding future demographic trends in the geographic unit.

Preclearance: Approval of a redistricting plan or other change in election procedures by a special three-judge federal district court in Washington, D.C., or by the U.S. Department of Justice under Section 5 of the Voting Rights Act.

Racially polarized voting: The term used to describe circumstances in which the voting preferences of a racial or ethnic group consistently vary from those of other racial or ethnic groups, particularly when the different voting preferences are based on the race of the candidate. Also referred to as "racial bloc voting."

Reapportionment: Reallocation of a fixed number of seats in a governmental body among established political units. Following each decennial census, the seats in the U.S. House of Representatives are reapportioned among the states. The result is that each state is assigned its number of congressional seats for the next decade. Reapportionment does not result in the establishment of new district boundaries. The term is sometimes used imprecisely to mean "redistricting."

RedAppl: The Texas Legislature's geographical information system (GIS) application used during the 1990s for redistricting. The system was available on only a small number of special GIS computer workstations located at the Texas Legislative Council.

RedAppl 2001: The Texas Legislature's geographical information system application as updated by the Texas Legislative Council for redistricting in 2001. The system will be available on PCs in members' Capitol offices.

Redistricting: The process of redefining the geographic boundaries of individual election units such as legislative or congressional districts or county election precincts.

RedViewer: A system for viewing maps of current districts and other redistricting plans over the Internet, available at the Texas Legislative Council's web site.

Retrogression: The term used to describe a reduction in the voting strength of a racial or ethnic group resulting from a redistricting plan or other change in election procedures. Retrogression is the primary test used for evaluating a change in election procedures under Section 5 of the Voting Rights Act.

Statistical sampling: The statistical method by which characteristics of a small group are measured and applied to the population as a whole.

Topologically Integrated Geographic Encoding and Referencing System (TIGER): The cartographic map database, prepared by the Census Bureau, that Texas will use as the geographic database for redistricting.

Total range of deviation: The range over which the populations of all districts in a redistricting plan deviate from the ideal district population.

Traditional districting principles: A term often used to refer to criteria, such as compactness and contiguity, that have historically been considered in drawing election districts.

Undercount: The error in census data that results from the failure to count some persons or housing units in the decennial census. Historically, certain groups, such as members of racial or ethnic minorities, have been disproportionately undercounted by the federal census.

Voting age population: The number of persons in a geographic unit who are at least 18 years of age. Because some population groups, such as racial or ethnic minorities, tend to be younger on average than the population as a whole, the voting age populations are frequently compared in evaluating the potential voting strength of those groups.

Voting Rights Act: The federal law prohibiting discrimination in voting practices on the basis of race or language group, codified as 42 U.S.C. Section 1973 et seq. The official title of the Act is the Voting Rights Act of 1965. Sections 2 and 5 of the Act are important for redistricting.

Section 2: Prohibits the adoption of voting standards or practices that abridge the right to vote on the basis of race or language group. This section applies to all states and other governmental units and may be used to challenge a redistricting plan that discriminates against a racial or language minority group.

Section 5: Requires that changes in election procedures (including changes in district lines) be precleared by the U.S. Department of Justice or by a three-judge federal district court in the District of Columbia before the changes are put into effect. Preclearance is granted only if the change is determined not to have the purpose or effect of denying or abridging the right to vote on the basis of race or language group. Only certain states, including Texas, and other jurisdictions are subject to Section 5.

Voting tabulation district (VTD): The census geographic equivalent of a county election precinct, created for the purpose of relating election data to census data. These VTDs often differ from actual election precincts because election precincts do not always follow census geography. During the approximation process that creates VTDs, county election precinct boundaries that do not follow census geography are assigned to the nearest census block boundary.