The Us Congressional Districts layer contains polygons for US Congressional Districts. The source for the information in this layer is the Los Angeles Registrar/Recorder's Precinct Information File (PIF), which is designed to match the Thomas Brothers TRNL (road network) layer.
Where boundaries are defined by streets, water, city boundaries, or other features, those arc segments are copied to the districts layer, so that the boundaries and other layer features match perfectly.

Supervisorial Districts as of the 2001 redistricting. These boundaries were approved by the County Board of Supervisors in 2001, and represent the boundaries of their political jurisdictions and those areas that vote for them.

2011 United States Congressional Districts clipped to the LA County Boundary.

This data was created by the California Citizen’s Redistricting Commission, and downloaded from their website. Click here to go to the site.

This data is based upon the US Census Bureau’s TIGER basemap, and are not the final version for the County. The TIGER file, while it represents physical features in the County accurately, does not have the same spatial accuracy as the County’s mapping layers. The Registrar/Recorder County Clerk is currently updating their precincts to include these new districts, and with the same precision as the County base.

However, the County has tested and found the Census Bureau’s data to substantially accurate for even large-scale mapping, so future changes will not dramatically impact mapping, but I do recommend coming back to this page to check for updates.

This layer contains the 2011 Official Supervisorial District Boundary for the County of Los Angeles, drawn at the parcel level, per Assessor parcels and the County Cadastral Landbase.

Purpose:
Supervisorial District Boundary maps for the County of Los Angeles

Supplemental Information:
Adopted September 27, 2011 – Another entry on this portal includes redistricting information from the Districts’ adoption in 2011, along with boundaries drawn at the TIGER street map level.

Per Sec. 21500 of the California Elections Code, Supervisor District boundaries are adjusted following each decennial federal census.

Published in the County Code under Title 1, Chapter 1.08, boundary descriptions are based on census tracts and city boundaries at the time of adoption.

Metes and Bounds descriptions were prepared by the Department of Public Works.

2010 Census Blocks provide more information and GIS data downloads on this portal. Census tracts listed in the County Code correspond to the first six digits of the GIS attribute CTCB10.

2011 California Board of Equalization Districts clipped to the LA County Boundary.

2011 California State Senate Districts clipped to the LA County Boundary.

The State Senate Districts layer contains polygons for California State Senate Districts. The source for the information in this layer is the Los Angeles Registrar/Recorder's Precinct Information File (PIF), which is designed to match the Thomas Brothers TRNL (road network) layer.
Where boundaries are defined by streets, water, city boundaries, or other features, those arc segments are copied to the districts layer, so that the boundaries and other layer features match perfectly.

The State Assembly Districts layer contains polygons for 2003 California State Assembly Districts. The source for the information in this layer is the Los Angeles Registrar/Recorder's Precinct Information File (PIF), which is designed to match the Thomas Brothers TRNL (road network) layer.
Where boundaries are defined by streets, water, city boundaries, or other features, those arc segments are copied to the districts layer, so that the boundaries and other layer features match perfectly.

Supervisorial Districts from 1991

School District Boundaries for Los Angeles County.

Please note: There are two types of school distrricts. The first type is a split district - a school district that separates the elementary school districts from the middle and high school district. The second type, a unified school district, combines all three types of schools.

In this dataset each unified district has its own polygon, and the split districts have a polygon for each combination of elementary and middle/high school district.