Methodology

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The left–right score is not ours. It is the first dimension of DW-NOMINATE, a scaling method developed by Keith Poole and Howard Rosenthal and maintained by Voteview (Jeffrey B. Lewis, Keith Poole, Howard Rosenthal, Adam Boche, Aaron Rudkin, and Luke Sonnet, UCLA). It places every legislator on a scale from roughly −1 (most liberal) to +1 (most conservative) using only how they voted on every roll call, and is comparable across the House and Senate and over time.

The second dimension (shown on the y-axis of the scatter charts) historically picks up cross-cutting issues (e.g. regional or establishment-vs-insurgent splits) and is harder to interpret.

Data used

• Members & scores: https://voteview.com/static/data/out/members/HS119_members.csv
• Roll calls: https://voteview.com/static/data/out/rollcalls/HS119_rollcalls.csv
• Individual votes: https://voteview.com/static/data/out/votes/HS119_votes.csv
• Photos: unitedstates/images (public domain, by Bioguide ID)

Coverage: House: 674 roll calls, latest 2026-09-16 · Senate: 915 roll calls, latest 2026-09-30. Voteview updates these files regularly as new votes are recorded; this site re-downloads them on every build.

Other figures

• Party unity: share of a member's Yea/Nay votes cast on the same side as the majority of their own party on that roll call (computed by this site; Independents are compared to other Independents).
• Chamber rank: position among current members, sorted from most liberal (#1) to most conservative.
• "No recent votes": members with no recorded vote in the 45 days before their chamber's latest roll call (typically resigned, died, or replaced).
• Vote codes: Voteview codes 1–3 = Yea, 4–6 = Nay, 7–8 = Present, 9 = Not voting.

State legislatures and executives

People (current state legislators, governors, lieutenant governors, attorneys general, secretaries of state and other statewide officials where recorded, plus committee memberships) come from the openstates/people repository (CC0), downloaded on every build — data as of commit 0360b5d278 (2026-10-24T00:49:28Z). Photos are linked directly from the image URLs recorded there (not stored on this server); some official sites block or remove them, in which case no photo is shown.

State roll-call votes come from the Open States monthly public PostgreSQL dump (https://data.openstates.org/postgres/monthly/2026-10-public.pgdump; extracted 2026-10-26 14:03 UTC). It is streamed once a month and only roll calls from legislative sessions starting on or after 2025-01-01 (the current two-year cycle) are kept. Individual votes are linked to legislators by Open States person IDs; votes Open States could not match to a person are ignored.

State left–right score (computed by this site): for each chamber, build a legislator × roll-call matrix (Yea = +1, Nay = −1, anything else missing). Drop lopsided roll calls where the losing side has under 2.5% of votes. Fit a one-dimensional linear ideal-point model, vote_ij ≈ a_j + b_j·x_i, on the observed entries by alternating least squares (equivalent to the first principal component of the vote matrix, handling missing votes), starting from the first SVD component. The scores x are oriented so the average Democrat is negative and the average Republican positive, then divided by the largest absolute score so the chamber spans −1 to +1. Members with fewer than 25 Yea/Nay votes on the retained roll calls are not scored or ranked; chambers with fewer than 20 contested roll calls are not scored.

Important: state scores are only comparable within one chamber of one state. A +0.5 in the Texas Senate is not the same as +0.5 in the Vermont House, and neither is comparable to the DW-NOMINATE scores used for Congress. The first dimension mostly captures the main party divide; in chambers with little partisan conflict it may reflect other splits. Party unity is computed as for Congress, on all Yea/Nay votes.

Executive branch

The Executive pages cover the President, Vice President, the heads of the 15 executive departments and Cabinet-level officials. Executives do not cast legislative votes, so these pages show other public records. All sources are re-fetched on every build; if a source fails, the last good copy is used.

• Roster (who holds each office, start date, portrait file): the current tables in Wikipedia's Cabinet of the United States article and the incumbent in President of the United States, via the Wikipedia API (fetched 2026-10-26 16:46 UTC). Names are cross-checked against whitehouse.gov/administration/cabinet and against Senate confirmation votes in Voteview; mismatches are flagged on the person's page. Party is as listed in each person's Wikipedia infobox.
• Portraits: official portraits hosted on Wikimedia Commons (mostly public-domain U.S. government works; license shown per page), stored on this server as 240px thumbnails.
• Presidential documents: the Federal Register API, all presidential documents (executive orders, proclamations, memoranda, notices, determinations, other) published since 2025-01-20; counted by signing date (fetched 2026-10-26 16:42 UTC).
• Vetoes: U.S. Senate, Vetoes by President Donald J. Trump (as of 2026-10-26; senate.gov often refuses automated requests, so a cached copy may be shown), with override votes from Voteview.
• Vice-presidential tie-breaking votes: derived from Voteview Senate roll calls (equal Yea/Nay among senators, question succeeded) and checked against the U.S. Senate's Votes to Break Ties in the Senate (as of 2026-10-26).
• Confirmation votes: Voteview Senate roll calls on nominations (PN numbers) whose description names the officeholder and the office; the latest such vote is shown. Officials confirmed by voice vote, serving in an acting capacity, or in posts that do not require confirmation show no vote.

Courts: U.S. Supreme Court

Roster: the current justices and the dates they took the judicial oath (“took seat”) are read from the Court's own Justices 1789 to Present table (justices with no end date), cross-checked against the Current Members page (fetched 2026-10-26). Appointing president, party of the appointing president and the Senate vote as recorded come from the Federal Judicial Center Biographical Directory; the Senate roll call itself is matched in Voteview's Senate roll-call file for the Congress in which the justice was confirmed. Portraits are lead images of each justice's Wikipedia article, used only when hosted on Wikimedia Commons (freely licensed or public domain); otherwise “No photo available” is shown.

Case votes: the justice-centered, citation-level Supreme Court Database (SCDB_2026_01, terms 1946-2025; Harold J. Spaeth, Lee Epstein, Andrew D. Martin, Jeffrey A. Segal, Theodore J. Ruger, Sara C. Benesh, Michael J. Nelson et al.). The SCDB site blocks automated downloads, so the release file is cached on this server and a new release is looked for once a month. For terms after the latest SCDB release, decided cases and per-justice votes come from the Oyez API (“majority”/“minority” votes). October Term 2026: 31 cases listed, 0 decided.

Majority / dissent rates: among cases a justice took part in, the share where SCDB's majority variable says they were in the majority (concurrences count as majority) or in dissent. Agreement: for every pair of current justices, the share of cases from the 2022–2025 terms (when all nine sat together; 246 cases) in which both were on the same side.

Left–right score for justices: Martin-Quinn scores (Andrew D. Martin and Kevin M. Quinn, 2002, Political Analysis) — the posterior mean ideal point per justice per term from a dynamic item-response model of the justices' votes, through the 2024 term. Negative = more liberal, positive = more conservative. The 95% range shown is the posterior 2.5–97.5 percentile. They are on a different scale than DW-NOMINATE and are not comparable with Congress scores.

Courts: federal judges

All sitting Article III judges below the Supreme Court come from the Federal Judicial Center Biographical Directory export (judges.csv and federal-judicial-service.csv; refreshed weekly, the cached copy is used if the download fails; latest commission date in the data: Oct 22, 2026). A judge is “sitting” when a service record has no termination and the judge is not deceased; “senior” when that record has a senior-status date. 1,453 judges (836 active, 617 senior) on 105 courts. Courts are grouped into circuits using 28 U.S.C. § 41. Appointing president, party of the appointing president, nomination/hearing/confirmation dates, the Senate vote type and ayes/nays, and the ABA rating are shown exactly as listed by the FJC; recent roll calls are linked to Voteview when one with the judge's name falls on the confirmation date. No left–right score is calculated for lower-court judges. Lower-court opinions are not collected: CourtListener's API requires a (free) account API token, which this site does not use, so pages say “Decision data not available here”.

Courts: state supreme courts

Current justices, office/seat, party label, date assumed office, appointing official, selection method, term length and founding year for the highest court of each state and D.C. are parsed from each court's Ballotpedia page (51 courts, 335 justices; retrieved Oct 26, 2026). Ballotpedia blocks automated requests from some servers, so the last good copy is cached and reused; a refresh is attempted weekly. Party labels are Ballotpedia's (most justices in appointed or nonpartisan systems are listed as “Nonpartisan”). Photos are Wikipedia lead images hosted on Wikimedia Commons, used only when the article mentions the state and a court (79 found); otherwise “No photo available”. No free, consistently coded source of state supreme court votes was found, so no decision data or score is shown (“No public decision data available for this court”). Lower state courts are not covered.

Caveats

Scores summarize voting patterns, not positions on any single issue; members with few votes have less certain scores. Bill descriptions come from Voteview's roll-call metadata and may be blank for procedural votes.