Data Sources

KingSt.com relies on publicly available data from official federal sources and established open-source projects. This page documents each source, what data it provides, how frequently KingSt.com refreshes it, and relevant quality considerations.

Senate LDA API

Source: lda.senate.gov/api/v1/filings/

What it provides: Quarterly lobbying disclosure filings submitted under the Lobbying Disclosure Act. Each filing contains the registrant (lobbying firm or self-filing organization), the client, reported lobbying income or expenses, general issue area codes, specific lobbying issue descriptions, individual lobbyists listed, and government entities contacted.

Refresh frequency: KingSt.com refreshes lobbying data after each quarterly filing deadline. Filings are due 20 days after the end of each calendar quarter (April 20, July 20, October 20, January 20). New data typically appears on the site within a few days of the filing deadline. Amendment filings, which can be submitted at any time, are captured in subsequent refreshes.

Data quality notes: Dollar amounts are self-reported and rounded to the nearest $10,000 for lobbying firms or $20,000 for organizations filing on their own behalf. The API provides structured access to filings dating back to 1999. Some older filings have inconsistent formatting. The API enforces rate limits, and KingSt.com respects these limits in its data pipeline.

Federal Election Commission (FEC)

Source: fec.gov/data/ (bulk downloads and API)

What it provides: Campaign finance data for all federal candidates, including itemized individual contributions, PAC contributions to candidates, candidate committee financial summaries, and independent expenditure reports. Individual contributions above $200 are itemized with the donor’s name, employer, occupation, and amount.

Refresh frequency: The FEC publishes updated bulk data files on a regular cycle. Candidate committees file quarterly reports (with pre-election reports in election years), and PACs file semi-annually or monthly depending on their designation. KingSt.com refreshes campaign finance data to align with FEC publication schedules, typically within a week of new bulk data availability.

Data quality notes: Contribution data is reported by campaigns and may contain typographical errors in donor names, employer information, and addresses. The FEC provides data as-reported and does not independently verify donor information. Contribution limits are enforced separately from the reporting process. FEC data does not include contributions to organizations that are not required to disclose donors (501(c)(4) organizations, for example), often referred to as “dark money.”

House Clerk — Roll Call Votes

Source: clerk.house.gov/evs/

What it provides: XML records of every roll call vote conducted in the U.S. House of Representatives. Each record includes the vote number, date, description, bill or resolution number, vote totals, and each member’s individual position (Yea, Nay, Not Voting, or Present).

Refresh frequency: KingSt.com checks for new House votes daily. Roll call vote XML files are typically published within hours of a vote being conducted. New votes appear on the site within a day of the official record’s publication.

Data quality notes: House Clerk vote data is considered authoritative. It is the official record of House votes. Occasional corrections are published by the Clerk’s office when recording errors occur, and KingSt.com incorporates these corrections on subsequent data refreshes. Vote descriptions are taken verbatim from the Clerk’s records and may be procedurally dense.

Senate.gov — Roll Call Votes

Source: senate.gov/legislative/votes.htm

What it provides: XML records of every roll call vote conducted in the U.S. Senate. Each record includes the vote number, session, date, description, vote totals, and each senator’s individual position.

Refresh frequency: KingSt.com checks for new Senate votes daily, matching the House vote schedule. Senate vote records are published shortly after each vote.

Data quality notes: Senate vote data is the official record and is considered authoritative. The XML format has remained stable across multiple Congresses. Vote descriptions for cloture motions, amendments, and nominations may require additional context to interpret — KingSt.com displays these descriptions as published by the Senate and provides supplementary information where available.

unitedstates/congress-legislators (GitHub)

Source: github.com/unitedstates/congress-legislators

What it provides: Biographical and service information for every member of Congress, past and present. This includes full names, party affiliations, state and district, terms of service with start and end dates, and unique identifiers used by other data systems (Bioguide ID, FEC ID, GovTrack ID, and others). The project also provides committee membership data.

Refresh frequency: KingSt.com syncs with this repository regularly. The community-maintained dataset is updated frequently, often within days of changes such as special elections, resignations, or party switches.

Data quality notes: This dataset is widely used across the civic technology community and is considered reliable. It is maintained by a community of contributors and has been in active development since 2013. Cross-referencing with multiple identifier systems makes it a useful bridge between data sources that use different member identification schemes.

OpenStates

Source: openstates.org

What it provides: State legislative data, including legislator information, bill tracking, and vote records for all 50 state legislatures, the District of Columbia, and U.S. territories. KingSt.com uses OpenStates data selectively to provide context on state-level legislative activity where relevant.

Refresh frequency: OpenStates data is refreshed on the schedule maintained by the OpenStates project, which varies by state. KingSt.com incorporates state-level data as it becomes available.

Data quality notes: State legislative data quality varies significantly across jurisdictions. Some states publish machine-readable legislative data promptly, while others rely on manual processes that introduce delays and formatting inconsistencies. OpenStates normalizes this data into a consistent format, but the underlying quality depends on each state’s data publication practices. Users should be aware that state-level data may be less complete or current than federal data.