MethodologySourcesConcept
Data sources
Where CapitolMath's bills, votes and legislators come from, and how often they're refreshed.
CapitolMath covers bills, legislators and roll-call votes in all 50 U.S. states and the U.S. Congress, along with committees, hearings and floor sessions where a legislature publishes them.
What's covered#
- Bills, their versions and their full action history.
- Legislators, their terms, committee seats and sponsorships.
- Roll-call votes, in committee and on the floor, with each member's vote.
- Committees, hearings and floor sessions, on the calendar.
Chambers are normalized to a common upper / lower vocabulary, so a filter on "upper chamber" means the Senate in most states and the same thing everywhere.
How fresh it is#
Each jurisdiction is refreshed on its own recurring schedule, and the derived measures — political lean, velocity and the bipartisan and popularity indices — are recomputed on every run.
Using the data#
The measures are computed estimates, not endorsements, and bulk redistribution isn't permitted. The full terms are in the terms of service; how we handle your own data is in the privacy policy and the trust center.