May 26, 2022

New Reference Tool: LegEx Uses Big Data to Track, Visualize Decades of Lawmaking in U.S. Congress (Free)

Word of a recently released free resource from the University of Washington.

From the Release Announcement:

University of Washington political scientist John Wilkerson has matched data visualization with the study of lawmaking to create a new online tool for researchers and students called the Legislative Explorer.

Think of it as big data meeting up with How a Bill Becomes a Law.

“The goal was to get beyond the ‘Schoolhouse Rock’ narrative and let users discover the lawmaking process for themselves,” said Wilkerson, UW professor of political science and director of the UW’s Center for American Politics and Public Policy.

The free tool is available at

The data set is huge indeed: The Legislative Explorer tracks the progress of every bill and resolution introduced in Congress since 1973 — 250,000 in all. It notes each time a bill or resolution advances from one stage of the process to the next, in or out of committee or moves to the floor for consideration, totaling about 750,000 such movements.


Users can drill down through the graphically presented data in lots of ways, including by type of legislation, sponsors, party or chamber of origin. The tool also has filters allowing users to sort results many ways, including by gender of sponsoring legislator, committee affiliation and — perhaps most helpful of all — whether the legislation is considered major or minor.

“The basic idea was to apply the data-driven discovery methods used increasingly in the natural sciences to bring big data to the lawmaking process,” Wilkerson said.

Wilkerson and collaborators suggest students or researchers might start by observing how many bills are introduced in each Congress and how many die along the way or are sent to the president and become law. They also suggest researchers should keep certain caveats in mind, including the reminder that bills vary in importance and get substantially changed or combined with others. The 906-page Affordable Care Act, Wilkerson noted, started out as a six-page bill on service members’ home ownership.


LegEx is a collaboration between the Center for American Politics and Public Policy at the University of Washington (John Wilkerson and Nicholas Stramp) and Schema (Christian Marc Schmidt and Sergei Larionov), a creative design and technology studio in Seattle. Both Wilkerson and Stramp have backgrounds in K-12 education.

The project was funded in part by revenue from LegSim, which provides tools for legislative simulation courses, and by the National Science Foundation.

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Gary Price ( is a librarian, writer, consultant, and frequent conference speaker based in the Washington D.C. metro area. Before launching INFOdocket, Price and Shirl Kennedy were the founders and senior editors at ResourceShelf and DocuTicker for 10 years. From 2006-2009 he was Director of Online Information Services at, and is currently a contributing editor at Search Engine Land.