TIGER/Line Shapefile, Current, State, Illinois, State Legislative District (SLD) Lower Chamber

This resource is a member of a series. The TIGER/Line shapefiles and related database files (.dbf) are an extract of selected geographic and cartographic information from the U.S. Census Bureau's Master Address File / Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) System (MTS). The MTS represents a seamless national file with no overlaps or gaps between parts, however, each TIGER/Line shapefile is designed to stand alone as an independent data set, or they can be combined to cover the entire nation. State Legislative Districts (SLDs) are the areas from which members are elected to state legislatures. The SLDs embody the upper (senate - SLDU) and lower (house - SLDL) chambers of the state legislature. Nebraska has a unicameral legislature, and the District of Columbia has a single council, both of which the Census Bureau treats as upper-chamber legislative areas for the purpose of data presentation; there are no data by SLDL for either Nebraska or the District of Columbia. A unique three-character census code, identified by state participants, is assigned to each SLDL within a state. States that had SLDL updates between the previous and current session include Georgia, Michigan, Minnesota, Montana, New York, North Carolina, North Dakota, Ohio, South Carolina, Washington, and Wisconsin. In Connecticut, Illinois, Louisiana, New Hampshire, Wisconsin, and Puerto Rico, the Redistricting Data Program (RDP) participant did not define the SLDLs to cover the entirety of the state or state equivalent area. In the areas with no SLDLs defined, the code "ZZZ" has been assigned, which is treated as a single SLDL for purposes of data presentation. There are no SLDL TIGER/Line shapefiles for the District of Columbia, Nebraska, and the Island Areas (American Samoa, Guam, the Commonwealth of the Northern Mariana Islands, and the U.S. Virgin Islands). The state legislative district boundaries reflect information provided to the Census Bureau by the states by May 31, 2024.

                                            {
  "fn": "U.S. Department of Commerce, U.S. Census Bureau, Geography Division",
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  "hasEmail": "mailto:geo.geography@census.gov"
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    "title": "tl_2025_17_sldl.zip",
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    "description": "The TIGER/Line Shapefiles are the fully supported, core geographic product from the U.S. Census Bureau. They are extracts of selected geographic and cartographic information from the U.S. Census Bureau's Master Address File/Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) System.",
    "downloadURL": "https://www2.census.gov/geo/tiger/TIGER2025/SLDL/tl_2025_17_sldl.zip",
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                                            [
  "State or equivalent entity",
  "Polygon",
  "Legislative District",
  "State or Equivalent Entity",
  "Illinois",
  "IL",
  "17"
]
                                        

                                            []
                                        

                                            {
  "name": "U.S. Department of Commerce, U.S. Census Bureau, Geography Division",
  "@type": "org:Organization"
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