MapLight's Core Work

Data Sets       Original Research       Custom Research       Projects

MapLight has three key strengths that, collectively, are not possessed by any other transparency or accountability organization:

  1. We possess a unique, proprietary data set of companies’ and organizations’ support for and opposition to bills in Congress, kept continually up-to-date by MapLight researchers.
  2. We combine multiple data sets in a large-scale way to systematically uncover connections between political inputs and political outputs – i.e. the impact of special interest influence.
  3. We proactively work to ensure that our data is used by accountablity actors such as journalists and advocacy groups to have real-world impact on policy and public debate.
Our website provides powerful tools for searching, sorting, and visualizing data, making influence connections that once required weeks of research to uncover available at the click of a mouse. By combining information that normally exists in "data silos" in a single database, we can systematically reveal political influence more quickly, comprehensively, and efficiently than was ever before possible.

Data Sets

Only MapLight produces a unique database combining lawmakers’ votes, groups supporting and opposing legislation, and campaign contributions—a database specifically developed to serve increased public accountability. 

Our Bill Positions API includes which interest groups, companies, and organizations support and oppose key bills in Congress. For each bill, our in-house research team uses public record sources, like congressional hearing testimony, news databases, and trade associations’ websites, to determine a bill’s supporters and opponents.

Our MapLight Federal Money and Politics Data Set is an easy-to-access, downloadable database featuring MapLight-enhanced Federal Election Commission campaign finance data and is available for free public use. The data set includes all federal contributions, independent expenditures, and candidate and committee totals, updated regularly with the most current data from the FEC.

Our Federal Lobbying Database provides timely information on unions, companies, and other organizations that are lobbying the federal government, including how much money has been spent, which firms have been hired, which issues have been lobbied on, who has been lobbied, and more. This data set is freely available via a searchable web tool and can be downloaded in a spreadsheet for deeper analysis.

The Personal Financial Disclosures Search brings to light the fiscal relationships linking legislators and private companies. Each year, members of Congress file "personal financial disclosures" (PFDs), detailed lists of their assets and sources of income, including investments. MapLight has compiled and organized these records into a free, searchable data set that can also be downloaded as a spreadsheet.

We have also refined a subset of the California Secretary of State's raw Cal-Access data into the MapLight California Money and Politics Bulk Data Set for quicker, easier use in analyzing contributions to candidates or ballot measure committees in California. The data set is downloadable and available for free public use.

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Original Research

We work alongside numerous groups who share an interest in transparency and/or political accountability. Most of these groups focus exclusively on tracking or providing public access to various forms of political inputs, such as data sets of campaign contributions or lobbying. Only MapLight is focused on connecting these political inputs to political outputs, such as the outcome of a particular vote, to systematically uncover and publicize instances of special interest influence.

MapLight conducts original research as part of our core work, using our database to uncover patterns of special interest influence on topics of high relevance to the public. We work closely with journalists, advocacy groups, and citizens to get this data in the news and into public debate in order to strengthen calls for transparency, accountability, and reform. 

Read MapLight's latest findings on money and influence here.

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Custom Research

MapLight develops our data, tools, and research services specifically to help journalists and nonprofit groups have public accountability impact. We offer custom research and training on our tools at no cost, provided that the resulting data is used for content that is free to the public.

Each year, MapLight’s research and communications teams fields hundreds of requests for custom money and politics data from journalists, nonprofit advocates, activist groups, and others. Our transparency tools and research services continue to be used by an ever-wider network of accountability actors to craft bold, urgent calls for change and reform.

See the latest news stories featuring MapLight research here.

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Voter's Edge

Voter's Edge is a one-stop shop for election research, providing citizens with nonpartisan information about candidates and ballot measures to empower them to vote in ways that reflect their interests. In 2014, Voter’s Edge covered every ballot measure, state candidate, and federal candidate in all 50 states, and MapLight partnered with the League of Women Voters of California Education Fund to give Californians access to personalized data on their federal, state, and local ballots, down to county, city, and school board races. During the 2014 elections, Voter’s Edge empowered more than one million site visitors. 728,000 people visited the site from California—the equivalent of one in 10 California voters that year.

For the 2016 elections, we have expanded our successful California pilot to Illinois and New York, providing nearly a quarter of the U.S. population with comprehensive information on their federal, state, and local races. 

Check out Voter's Edge now to get informed about the candidates and measures on your ballot.

Voter's Edge

Quick Guide to Props

In time for the 2016 general election, MapLight partnered with the California Secretary of State to launch the Quick Guide to Props, an easy way for California voters to cut through campaign noise to get informed about who's funding state ballot measures and what the measures would do. Now live on the Secretary of State's website, the tool provides voters with brief summaries of every measure, condensed “pro” and “con” arguments, and data on who is funding “Yes” and “No” campaigns, including top campaign contributions during the election cycle and contribution totals—updated daily through the election.

Visit the Quick Guide to Props today to learn more about California ballot measures.

Dark Money Watch

Dark Money Watch is a hub for knowledge about dark money—outside election spending by hidden donors—which is a growing force in U.S. politics. Combining top online data sources with MapLight's own reporting on this secret political spending, the site makes it easy to learn how dark money works, explore who is behind it, read the latest dark money news, and dig into data to help expose this shadowy political practice.

Learn more by exploring the website and following Dark Money Watch on Facebook and Twitter.

Dark Money Watch Home Page

Cal-Access Campaign Finance Data

In September 2015, MapLight launched a new campaign finance search engine in collaboration with the California Secretary of State’s office. Power Search is now live on the Secretary of State’s website—a major victory for transparency in the state. Thanks to the intuitive design of this new tool, anyone can quickly and easily access and analyze California campaign finance data from Cal-Access on any device. Built as open-source software, Power Search can easily be adapted for other jurisdictions, setting a new standard in open government technology.

In addition, we recently released a search tool for independent expenditures in California, shedding light on outside spending by companies, individuals, political parties, unions, and trade associations to support or oppose candidates and ballot measures in the state. This tool is now part of Power Search on the California Secretary of State's website.

Visit Power Search today to follow the money in California politics.

Power Search

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Learn more about MapLight's impact.