Redistricting Data – a Basic Overview

8/14/2019 Redistricting Data a Basic Overview

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Redistricting Data A Basic Overview

Karin Mac DonaldStatewide DatabaseUC Berkeleyhttp://[email protected]
http://swdb.berkeley.edu/mailto:[email protected]:[email protected]://swdb.berkeley.edu/


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Why are we talking about data?

Redistricting = the drawing of electoral boundaries& meeting certain criteria

Criteria? - U.S. Constitution- Federal Voting Rights Act- CA Proposition 11


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(2) Districts shall comply with the federal Voting Rights Act (42U.S.C. Sec.

1971 and following).

(3) Districts shall be geographically contiguous.(4) The geographic integrity of any city, county, city and county,

neighborhood, or community of interest shall be respected to the extent

possible without violating the requirements of any of the preceding

subdivisions. Communities of interest shall not include relationships with

political parties, incumbents, or political candidates.

(5) To the extent practicable, and where this does not conflict with the criteriaabove, districts shall be drawn to encourage geographical compactness such

that nearby areas of population are not bypassed for more distant population.

more criteria:


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and data used

Equal population: Census Data (PL94-171)

Geography: Census Blocks

Voting Rights Act: Census Data + Statement of Vote +

Statement of Registration

Geography: Census Blocks, Election Precincts

Contiguity: Census Geography

Respect for Cities & Counties: Census Geography

Respect for Neighborhoods and Communities of Interest:

Public Testimony and Submissions, alternative data sources, i.e.neighborhood boundary map from city?


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District Building Blocks: U.S. Census Geography

1990: 58 Counties

471 Census Places/ Cities

5,874 Census Tracts

400,414 Census Blocks

2000: 58 Counties1,018 Census Places/ Cities

7,049 Census Tracts

533,163 Census Blocks

2010: 58 Counties

? Census Places/ Cities? Census Tracts

? Census Blocks


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Census Blocks and Tracts


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Examples of Data by Census Block:


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and more about data by census block:

PL 94-171 / Census

Data reported include: - population

- voting age

- race/ethnicity

SOR~ Statement of Registration

Data reported include: -Total Registration

-Party affiliation

-Sex

-Age

SOV~ Statement of Vote

Data reported include: - Total Vote

- Votes for candidates

- Votes for propositions


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A note about precincts:


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and this is why you are happy about data on the

census block:


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Data that are not commonly available:

Communities of Interest:

What is a Community of Interest? It depends

Group of people with specific common interest

Can be defined geographically

Needs to be documented and brought to commissions attentionWhat are they NOT?

Communities of interest shall not include relationships with

political parties, incumbents, or political candidates

Neighborhoods:

Vary in size

Are sometimes defined by cities, sometimes by communities

No data sources available that show neighborhoods in CA

Need to be documented and brought to commissions attention


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Community of Interest and Neighborhood:


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Data to document a Community of Interest or

Neighborhood: an example

Create a map of the boundaries (use Google maps if no GIS

available)

Outline what defines the Community of Interest:

What is your mission or your commonality

Show that your members live within the boundaries

Explain what is different outside of the boundaries of your

Community of Interest

Explain why it is important to be kept whole, and how it would be

a disadvantage to be split by an electoral boundary line

Testify, submit written testimony, send supporting information to the

commission.

Redistricting Data – a Basic Overview

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