Data source: National Institute on Money in State Politics
Our database includes campaign contributions given to each member of the 2009-2010 and 2011-2012 California State Legislatures since January 1, 2003. We include all contributions by donors giving $100 or more to one candidate.
Candidates and contributors periodically file campaign disclosure statements with the Secretary of State's office, as required by law. Our partner group, the National Institute on Money in State Politics (NIMSP), obtains this data from the Secretary of State's office and "cleans it up" to make it more useful for analysis. NIMSP standardizes contributor names and categorizes each contribution according to the interest group of the donor. NIMSP provides this cleaned-up data to MapLight and other groups about every three months.
Interest Group categories
NIMSP tags (categorizes) each contribution according to the industry of the donor, using a taxonomy of the 400-odd interests that give money to politics. For example, contributions from the Hollywood Park Casino and personal contributions from Curren Price, Vice President of that casino, are both tagged as "Casinos, racetracks, & gambling." On our site we call these categories "interest groups" or "interests."
This interest-group categorization allows research on overall trends, such as patterns of contributions from oil interests. On the MapLight site you can view individual contributions—who gave what to whom, on what date—or you can view contributions aggregated by interest group.
These interest group categories make up a three-level hierarchy, with some interest groups being part of others. For example, the interest group category Petroleum refining & marketing is part of the larger category Oil & Gas, which is part of the still larger category Energy & Natural Resources. This hierarchical system makes it possible to examine both specific industries and larger trends. (Browse the Interest Groups section of our site to see all the categories and how they fit together.)