Corpus types

corpusType chooses which body of law a search runs against. It is the single most important filter in the API: it decides whether you get a statute, a regulation, a court rule, agency guidance or a decided case.

{ "query": "security deposit return", "corpusType": "STATE", "state": "ca" }

Pass one token or a list. This page is the query vocabulary: what each token means and how to scope it. For how much data sits behind each one and what is deliberately excluded, see API Coverage.

Scoping rules

A federal token needs only corpusType

{"query": "civil rights under color of law", "corpusType": "USC"}

A state token needs corpusType and state

Omit state on a state-scoped token and the search spans every jurisdiction that has that corpus ingested, which is rarely what you want and always costs the same.

{"query": "security deposit return", "corpusType": "STATE", "state": "ca"}

state also accepts a list, so one call can cover several jurisdictions.

Narrow further with source, where a token folds in several bodies

{"query": "tip credit", "corpusType": "AGENCY_GUIDANCE", "source": "whd_foh"}

titleNumber is only valid alongside corpusType USC or CFR. Sending it with any other token returns a 422.

The 19 tokens

Sizes are distinct sections, measured 2026-09-07. Call GET /us/statutes/coverage for a live figure and for which tokens have data in which jurisdiction.

Federal-scoped

Token	Contains	Sections
`USC`	United States Code, the codified federal statutes	60,170
`SESSION_LAW`	Statutes at Large: public and private laws as enacted, 1789-2026	423,928
`STATUTE_COMPILATION`	An act’s own text as amended through a stated later public law	80,232
`CFR`	Code of Federal Regulations, the continuously refreshed current compilation	222,251
`CFR_ANNUAL`	GPO’s published annual editions of the CFR, 31 editions, 1996-2026	312,132
`FEDERAL_REGISTER`	Federal Register agency rules, final and proposed	196,237
`FEDERAL_REGISTER_NOTICE`	A curated slice of Federal Register notices, those acting on a rulemaking	17,616
`EXECUTIVE_ACTION`	Presidential documents: executive orders, proclamations, memoranda	3,643
`AGENCY_GUIDANCE`	Sub-regulatory guidance from 51 named sources across 26 agencies	81,451
`AGENCY_ADJUDICATION`	Federal matters decided by an agency, seven bodies	100,920
`US_TAX_TREATY`	Bilateral income tax treaties, Treasury explanations, the Senate treaty record	1,649
`SENTENCING_GUIDELINES`	US Sentencing Guidelines, current sections plus former text in Appendix B	1,281
`FEDERAL_RULES`	Federal Rules of Civil, Criminal, Appellate and Bankruptcy Procedure, Evidence, and Supreme Court Rules	589
`CONSTITUTION`	US Constitution, Articles and Amendments	74

State-scoped

Each of these requires state, or spans every jurisdiction holding that corpus.

Token	Contains	Sections	Jurisdictions
`STATE`	State statutory codes	1,934,326	52
`REGULATION`	State administrative codes	1,467,452	52
`STATE_RULES`	State court rules: civil, criminal, appellate, evidence, professional conduct, local	53,638	46
`STATE_AGENCY_GUIDANCE`	State regulator guidance, almost all insurance bulletins	13,334	49
`STATE_CONSTITUTION`	State constitutions	12,762	51

Choosing between tokens that look alike

Five pairs are routinely confused, and picking the wrong one returns a confident answer to a different question.

You want	Use	Not
What federal law says today	`USC`	`SESSION_LAW`, which is law as enacted and never updated
The text of an act Congress passed	`SESSION_LAW`	`USC`, which rearranges it by subject
An act that was never codified	`STATUTE_COMPILATION`	`USC`, which has no address for it
A regulation as it reads now	`CFR`	`CFR_ANNUAL`, which is a past published edition
What a regulation said in 2004	`CFR_ANNUAL`	`CFR` with `asOf`, which reconstructs rather than reproduces
What an agency thinks a rule means	`AGENCY_GUIDANCE`	`AGENCY_ADJUDICATION`, which is decided cases
How an agency decided a case	`AGENCY_ADJUDICATION`	`AGENCY_GUIDANCE`

For asking any corpus what it said on a past date, see Point-in-time law. SESSION_LAW and STATUTE_COMPILATION both carry goodLawStatus: "unknown" by design: they are historical records, not statements of current law.

Filtering to one named source

AGENCY_GUIDANCE, AGENCY_ADJUDICATION, FEDERAL_RULES, CFR, US_TAX_TREATY and STATE_AGENCY_GUIDANCE each fold several independently filterable bodies into one token. Every result carries a source field naming which one it came from; pass that value back as the source filter to scope to it.

{ "query": "petition for writ of certiorari", "corpusType": "FEDERAL_RULES", "source": "sct" }

source accepts a single value or a list, so source: ["frcp", "sct"] searches both in one call. An unrecognized value is rejected with 422 and the error names every valid code, so the API itself is the authoritative list.

Token	Sources
`FEDERAL_RULES`	`frcp`, `frcrp`, `fre`, `frap`, `frbp`, `sct`
`CFR`	`far` (48 C.F.R. ch. 1), `dfars` (ch. 2). Every other CFR result has a null `source`.
`AGENCY_GUIDANCE`	51 codes. See the source registry.
`AGENCY_ADJUDICATION`	7 bodies. See Federal coverage.
`US_TAX_TREATY`	`us_tax_treaty`, `us_tax_treaty_technical_explanation`, `senate_treaty`, `senate_treaty_resolution`, `senate_treaty_document`
`STATE_AGENCY_GUIDANCE`	`state_insurance_bulletin`, `state_financial_bulletin`

The far and dfars sources split existing Title 48 data by chapter. They are not a separate ingest and do not add sections to the CFR total.

API Coverage

How much sits behind each token, and what each corpus deliberately excludes.

Jurisdictions and state codes

The 52 jurisdictions and how to discover live coverage.

DATA COVERAGE

USE CASES

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CORE CONCEPTS

LAW CHANGE ALERTS

WORKING WITH THE API

GROUNDING AI

RECIPES

Scoping rules

The 19 tokens

Federal-scoped

State-scoped

Choosing between tokens that look alike

Filtering to one named source

API Coverage

Jurisdictions and state codes

​Scoping rules

​The 19 tokens

​Federal-scoped

​State-scoped

​Choosing between tokens that look alike

​Filtering to one named source

​Related

API Coverage

Jurisdictions and state codes

Scoping rules

The 19 tokens

Federal-scoped

State-scoped

Choosing between tokens that look alike

Filtering to one named source

Related