U.S. Bureau of the Census
Census Redistricting Data Program (Public Law 94-171)
What is the purpose of this program?
To provide state governments with small-area census population counts to support congressional and legislative redistricting after each decennial census.
What are its origins?
Following the "one-person, one-vote" court decisions in the 1960s, states found 1970 census small geographic areas to have boundaries that did not coincide with voting district lines. This frustrated their efforts to match local voting districts (precincts) with small-area census areas to create congressional & legislative districts with balanced populations.
The Census Bureau, National Conference of State Legislatures, and state officials began in 1972 to design a 1980 census program to meet this critical need. This cooperative effort was used as well for planning the 1990 and 2000 Programs.
What does Public Law 94-171 require?
In 1975, Congress enacted Public Law 94-171, which amended the Census Law (Title 13, United States Code) setting up the following requirements:
- The Census Bureau is to inform state governments at least 4 years before each census of technical guidelines they must follow to obtain population counts for their locally defined voting districts (e.g. precincts) based on the decennial census.
- States wishing to participate in this nonpartisan, voluntary program are to submit to the Census Bureau the specific boundaries of their voting districts, following technical criteria established by the Bureau.
- The Census Bureau must provide small area population totals to the legislature and governor of each state, in a nonpartisan manner, by one year after the census (i.e. by April 1, 2001)
In 1995 state officials were invited to participate in the 2000 Census Redistricting Date Program:
Phase 1, Block Boundary Suggestion Project (BBSP)
State officials suggest roads, rivers, streets, ridgelines, and so forth that correspond to the boundaries of their voting districts. The Census Bureau then uses the acceptable, visible ground features to design blocks so that the blocks can subsequently be used to define the boundaries for voting districts. Phase 1 activity: 1995-1998
Phase 2, Voting District Project (VTDP)
The Census Bureau sends maps to all participating states in early 1999. States are given the opportunity to outline their voting districts in accordance with Census Bureau guidelines. Participants then return the maps (or electronic files) to the Census Bureau so that 2000 census maps and population totals can be prepared for each designated voting district. Phase 2 activity: 1999.
Phase 3, Data Delivery
All state legislatures and governors receive 2000 census population counts broken down by race groups and Hispanic origin for the total population and for persons 18 years and older.
All states receive these data for standard tabulation areas e.g., counties, cities, census tracts) and for each census block. In addition, states that participated in Phase 2 receive these data for each voting district they specified in accordance with the Census Bureau's technical criteria.
Census maps showing the boundaries of counties, cities, census statistical areas, blocks, and voting districts will accompany these data. Phase 3 activity: January to April 1, 2001.
U.S. Bureau of the Census, Census 2000
Redistricting Data Office
Maryland Department of Planning, Planning Data Services
State Board of Election Laws
Department of Legislative Services
This page was last updated: 2011-05-25