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US laws for your AI agents, your legal AI, your research platform and your compliance tools.
Vaquill AI is the open API for US primary law: statutes, regulations, court rules, agency guidance, adjudications, executive orders, session laws, with source links.
Free credits for personal projects, student work, and academic research.
- 5.4M+
- primary-law sections
- 56
- US jurisdictions
- 3
- access paths: REST, MCP and SQL
Trusted by 1,300+ accounts across 150+ organizations, including YC-backed companies
Constellate
Readiness Systems
- Brent Resh Law, PLLC
- The New Firm, Ltd.
In their words
Vaquill is the piece that made statutes verifiable rather than merely findable.
Brent M. ReshAttorneyBrent Resh Law PLLC
Read the storyEvery US jurisdiction, in one consistent format.
60,494
US Code sections
222,311
CFR sections
196,816
Federal Register rules
2M+
State statute sections
425,427
Statutes at Large
Federal law as enacted, 1789 to 2026
31
CFR annual editions
312,132 sections observed at published dates, since 1996
96,966
Agency guidance documents
53 named sources across 26 agencies
100,920
Agency adjudications
Seven federal tribunals, served as issued
20,604
State session laws, as passed
2025 sessions, 50 jurisdictions
A code tells you what the law says now. A session law tells you what changed and when: every act from the 2025 sessions comes with the date it was signed, the dates it takes effect, and its text as passed, including the words it struck out. In 11 jurisdictions it also lists the code sections the act changed, so a change is visible before the code is updated. Indiana and Tennessee are not held, and Delaware, Oklahoma and Colorado are partial.
How session laws workStatutes
Statutes + regulations
Statutes + regulations + constitution
Federal agency guidance
How agencies say they read their own rules: 53 named sources across 26 agencies, each one filterable on its own. Guidance is not binding law, and it is stored separately from law that is.
See all 53 sources
Internal Revenue Service
- Revenue Procedures
- Revenue Rulings
- Notices
- Announcements
- Internal Revenue Manual (procedure, not law)
- Written Determinations (PLR, TAM, CCA - not precedent)
Centers for Medicare & Medicaid Services
- Medicare Internet-Only Manuals (procedure, not law)
Department of Justice
- Justice Manual
- Antitrust Division Business Review Letters
- Antitrust Division Leniency Policy
- DOJ & FTC Merger Guidelines
Federal Trade Commission
- Advisory Opinions
- Policy Statements
US Copyright Office
- Circulars
- Compendium of Copyright Office Practices (Third)
Department of Labor, Wage and Hour Division
- Opinion, Ruling and Administrator Interpretation Letters
- Field Operations Handbook
Equal Employment Opportunity Commission
- Enforcement and Policy Guidance, incl. Compliance Manual
Treasury, Office of Foreign Assets Control
- Sanctions FAQs, with prior versions
Financial Crimes Enforcement Network
- Administrative Rulings
- Guidance (alerts, advisories, notices)
- Beneficial Ownership Information FAQs
- BOI Rulemaking Q&As
- Small Entity Compliance Guide
- AML Act of 2020 implementation material
Consumer Financial Protection Bureau
- Consumer Financial Protection Circulars
- Supervisory Guidance
Social Security Administration
- Rulings
US Patent and Trademark Office
- Manual of Patent Examining Procedure (MPEP)
- Trademark Manual of Examining Procedure (TMEP)
US Citizenship and Immigration Services
- Policy Manual
National Labor Relations Board
- General Counsel Memoranda
- Division of Advice Memoranda
Commodity Futures Trading Commission
- Staff Letters (no-action, exemptive, interpretative)
Federal Reserve
- Supervision & Regulation (SR) and Consumer Affairs (CA) Letters
Office of the Comptroller of the Currency
- Bulletins
- Interpretive Letters
Federal Deposit Insurance Corporation
- Financial Institution Letters (FILs)
Health and Human Services, Office for Civil Rights
- HIPAA Guidance
- HIPAA FAQs
- Resolution Agreements & Civil Money Penalties
Consumer Product Safety Commission
- Office of General Counsel Advisory Opinions
- Small Entity Compliance Guides
Bureau of Industry and Security
- Advisory Opinions (Export Administration Regulations)
Directorate of Defense Trade Controls
- Commodity Jurisdiction Determinations
- Policy Guidance
Department of Defense
- DFARS Procedures, Guidance and Information (PGI)
Federal Communications Commission
- Declaratory Rulings
Federal Energy Regulatory Commission
- Policy Statements
Department of Energy
- Appliance Standards Guidance and FAQs
Federal administrative adjudications
Decisions from executive-branch tribunals, served as they were issued. No publisher in this family marks when a later decision overrules an earlier one, so we do not tell you either. Check these the way you would check any decision.
- FTC Part 3 administrative filings
- SEC Commission opinions and adjudicatory orders
- Merit Systems Protection Board (MSPB)
- Board of Immigration Appeals and Attorney General (I&N Dec.)
- NLRB Board decisions
- DOJ Office of Legal Counsel opinions
- CFPB enforcement actions
Federal courts' own rules
6,234 local rules from 52 rule sets: the 13 courts of appeals, the federal habeas rules, six national courts such as the Tax Court and the Court of Federal Claims, and 32 district courts, each from the court's own site. These are separate from the national Federal Rules of Procedure, which are held as well.
- CFR
- Refreshed daily
- US Code
- Refreshed weekly
- State regulations
- Refreshed monthly
- Every source
- Pulled from the jurisdiction's own official publisher
Four ways to reach the corpus.
REST
The hosted API.
If your product looks up law a section at a time.
MCP
The same corpus inside an agent.
If you want Claude or Cursor to look the law up for you, no code.
SQL over the object store
Query the corpus as a database.
If you would rather hold the data yourself and query it.
Vector index
Skip rebuilding retrieval.
If you are building AI search and do not want to index 5M sections yourself.
Try the database claim. This runs against the public object store with no key and no download.
-- No download, no key. DuckDB reads the object store over HTTPS.
INSTALL httpfs; LOAD httpfs;
SELECT citation, section_title, word_count
FROM read_parquet('https://oss-data-us.vaquill.ai/v2026.09.1/us_ak_constitutions.parquet')
WHERE section_title ILIKE '%search%';- Citation in, section out
- Bluebook and the form a state’s own courts print. 42 U.S.C. § 1983, Cal. Civ. Code § 1946.2, MCR 3.709 and N.D.R.Civ.P. 64 all resolve to one exact provision.
- Point-in-time
- Pass asOf to read a section as it stood on a past date. Every answer says whether it came from a published edition or a reconstruction.
- Change alerts
- Watch a section or a whole corpus. Signed webhooks and email when the text moves, with the old and new text attached.
- Formats per section
- Styled HTML, plain text, the publisher’s own PDF and XML, and DOCX where the source offers one.
From key to cited law in one call.
request.sh
curl -G https://api.vaquill.ai/api/v1/us/statutes/resolve \
-H "Authorization: Bearer $VAQUILL_API_KEY" \
--data-urlencode "cite=42 U.S.C. § 1983"Title 42 › Chapter 21 › Subchapter I › § 1983
§ 1983. Civil action for deprivation of rights
42 U.S.C. § 1983 (2024)
US CodeFederal2024 editionIn force
…officer's judicial capacity, injunctive relief shall not be granted unless a declaratory decree was violated or declaratory relief was unavailable. 1979—Pub. L. 96–170 inserted “or the District of Columbia” after “Territory”, and provisions relating to Acts of Congress applicable solely to the District of Columbia.
Last amended 1996 · 2 amendments · Pub. L. 104-317, Pub. L. 96-170
response.json
1. Get your key→2. Call the endpoint→3. Ship cited law
Two things you get without building them.
Law Change Alerts
Learn more
Usage-based credits, not seats.
Pro
Where most builds start.
- 20,000 API credits included every month
- Up to 2 API keys Enough for a live key and a test key.
- Attribution required A visible "Legal data by Vaquill AI" credit, linked to our site, wherever our data reaches your users.
- Named as a customer Your name and logo identify you as a Vaquill AI customer on our site and in our marketing.
- Law change alerts by email
- Email support
Bootstrapped, under 10 people?
Business at a reduced rate. Email contact@vaquill.ai and tell us about your team.
Who this is for
- ·Businesses testing us as their data backend
- ·Lawyers verifying answers in Claude or ChatGPT
- ·Developers evaluating coverage before they build
Business
For shipping our data inside your product.
- 200,000 API credits included every month
- Up to 10 API keys
- Invite your team
- Law change alerts by webhook Signed webhooks and up to 100 watches.
- Point-in-time state law Read a section as it stood on a past date, rebuilt from the changes we have tracked.
- Statute intelligence The same provision in every other US jurisdiction, what cites it, and its defined terms.
- Attribution waived Ship our data in your product under your own brand.
- Priority support
Who this is for
- ·Legal tech products serving their own users
- ·Compliance platforms tracking every US jurisdiction
- ·AI teams grounding agents at scale
Not building a business on it yet? Personal projects, student work, and academic research get free credits. Email contact@vaquill.ai with what you are building.
What a license gives you
- Full corpus daily sync into your own database
- The source PDFs and text files we collect
- Train and fine-tune on all of it
- Redistribution and white-label terms in writing
- Volume pricing, custom SLA, and invoicing
Common questions
US primary law other than case law: statutes, regulations, constitutions, court rules, executive orders, agency guidance, and agency adjudications. Federal plus all 50 states, DC, Puerto Rico, Guam, the Northern Mariana Islands, the US Virgin Islands and American Samoa, about 5.4M+ sections. State session laws, the acts as each legislature passed them, are served alongside: 20,604 acts from the 2025 sessions across 50 jurisdictions, with signing and effective dates. The coverage section above breaks it down corpus by corpus, and GET /api/v1/us/statutes/coverage returns the live numbers.
Need a source we don't cover yet?
A specific set of government PDFs, or a slice of administrative law shaped for your product. Turning messy government data into clean, structured law is the whole job here, so bring us the hard ones.
contact@vaquill.aiWorking in legal aid or civil justice?
Verified nonprofit legal aid and public interest organizations get the full API free, with the same corpus and the same endpoints as every paid plan.
Apply for free access