Finding the data you need from state and local governments can be very challenging. Some states are more interested in sharing data than others. You can’t count on every state or local government to have an open data portal, or on finding someone in the local government to help you find what you need or address your questions.
U.S. states
Start your search for state-specific data the easy way with an online search for your state’s data portal. If that turns up nothing, check the federal data portal and look for a link for your state.
If you find no sign of a portal, that doesn’t mean that your state doesn’t have data to share. You’ll just have to work harder to find what you need. Check the state’s website for information about your state agencies. If you don’t find what you need online, start calling agencies by phone. Be prepared to explain what you need.
Your state may have a librarian who can help you understand how to locate information. Librarians at your local library may also be able to advise you on navigating government information sources. Be polite and persistent; state agencies are not always responsive about data requests.
Every U.S. state, as well as the District of Columbia, has an open records law similar to the federal Freedom of Information Act. If you’re having trouble getting data that you know (or have good reason to believe) exists, you can request the information through the rights guaranteed to you by these laws.
Pew Charitable Trusts
The Pew Charitable Trusts is a good nonprofit source for research and other information about U.S. states. It conducts research and reporting across all states and the District of Columbia.
U.S. counties
Most counties don’t yet have centralized open data portals, but some, like Illinois’ Cook County, do. Try an online search for one when you start looking for data. The next place to check is the county open data portal list on Data.gov.
Chances are, your county won’t make it easy for you, so it may take some time to locate the data you seek. Call county offices and explain your needs. Don’t be surprised if you have trouble reaching someone who seems to understand your request, but keep asking around. Try speaking with a local librarian for advice on obtaining local government data.
If all else fails, talk with the staff at the office of your local government representatives (local to the source of the data you need). Many of them deal with similar challenges obtaining data all the time and can offer advice or other help with the process.
Remember that these offices exist to serve constituents, so if you don’t live in the area, mention a little about how your work helps the locals. If your work might lead to new businesses, employment, or any economic benefit for the area, be sure to say so!
U.S. cities
Many cities are establishing open data portals now. You may find yours easily in an online search, especially if you are interested in a large city. You can also find a list of city portals on Data.gov.
Here are some of the established big-city data portals:
County and city governments collect a lot of transactional data — records about government activity such as building permits, property transfers, licenses, and tax payments. But they don’t usually gather and share much information about people and how they live. If you are interested in demographics, cost of living, lifestyle, and so on, you may get more relevant data from the federal government or a commercial data supplier.