Cicero - Learn - Web API for legislative district matching

Use an address to look up any legislative district, along with its geography and elected representative

Elected Official Data
District ID and Contact Information

Look up detailed legislative contact information and district boundary data for elected officials at several levels of legislature:

Local - More than 70 local city councils in the United States and Canada
State - Legislative data for US state house and senate legislatures and Canadian provincial and territorial assemblies
National - Legislative data for the United States Senate and Congress, Canadian Parliament, Australian Parliament, and New Zealand Parliament
Coming Soon... France, UK and India...

For a list of the local, state and national legislative bodies available through Cicero, click here.

Retrieve valuable and accurate data* for each legislator including:

Legislator's mailing address information
Legislator's phone and fax numbers
Legislator's e-mail addresses and URLs
Legislator's party and committee data
Legislator's district ID, and more

Match addresses to non-legislative districts throughout the U.S.

Watersheds
School districts
Counties
Police districts (for most major metropolitan areas)

District Maps
Maps of Legislative District Boundaries

The Cicero Web Services API generates a district map image for each of the districts resulting from an address lookup. Legislative district maps help visually describe the geographic area an elected official represents. You can use district map images to:

Make customized and interactive maps by integrating Cicero into many widely available web services frameworks
Display legislative district maps on your website
Enhance reports and presentations with maps describing relevant legislative district boundaries
Add visual impact to e-mail, call-to-action, fundraising or advocacy campaigns

Want to see maps of a variety of legislative districts? Try Cicero Live.

* As general elections, special elections, and redistricting initiatives take place, the Cicero team – made up of both geographers and GIS software developers – conducts continual elected official data and district boundary updates. Learn about the latest additions on the Cicero News page.

Address-Level Legislative District Identification

In this example, Cicero accurately places an address in Pennsylvania House District 175. By contrast, a ZIP code-based geocoder would mistakenly locate the same address in PA House District 181— the legislative district in which the centroid of ZIP code 19123 is located.

Cicero uses address-level geocoding - the most precise method of geocoding. Most other lookup services use ZIP code-level geocoding. Cicero accurately places constituents and stakeholders in their legislative districts.

Why do we use address-level geocoding rather than ZIP code-level geocoding?

Address-level geocoding pinpoints addresses on a street level map unlike ZIP code geocoding which uses the centroid of a ZIP code zone as the reference point for all addresses within that ZIP code.
Street-level data fit neatly within even the smallest legislative districts, accurately linking citizens to their national, state and local elected officials.
In many cases, ZIP code boundaries don’t match legislative district boundaries. In fact, ZIP code zones are larger than many city council districts. Using ZIP code geocoding in these cases returns large numbers of incorrectly geocoded addresses – assigned to an incorrect legislative district, and consequently the wrong elected officials.

Documentation

Cicero Product Sheet

Gerrymandering Index White Paper

Redrawing the Map on Redistricting 2010: A National Study

Cicero Data Availability