Federal Rules of Procedure API: FRCP, FRE, FRAP, FRCrP, FRBP and Supreme Court Rules

The federal rules of procedure are available as a queryable corpus at corpusType=FEDERAL_RULES, holding 1,130 sections across six rule sets (all but the Supreme Court Rules are held in two printings, explained below): the Federal Rules of Civil Procedure, Criminal Procedure, Evidence, Appellate Procedure, and Bankruptcy Procedure, plus the Rules of the Supreme Court of the United States. The Supplemental Rules for Admiralty or Maritime Claims and for Social Security Actions are in there too, under the civil rules' frcp code. Each set is filterable by a source code, so you can scope a query to evidence law without dragging in bankruptcy timing rules. It is one of the smallest federal corpora we serve, and litigation software touches these rules on almost every screen.

Reviewed and corrected on 12 October 2026. This is general information, not legal advice.

Disclosure: we build Vaquill AI, a US primary law API. The coverage endpoint that reports the corpus numbers below is free, so nothing here has to be taken on trust.

TL;DR

• 1,130 sections, corpusType=FEDERAL_RULES, on a monthly board cadence. Small corpus, heavy usage, because deadline math and evidentiary objections run through it constantly. The total counts every set except the Supreme Court Rules twice: once as the courts publish it and once as printed in the appendix to the relevant title of the US Code.
• Six source codes: frcp, frcrp, fre, frap, frbp, sct. The Supplemental Admiralty Rules and the Supplemental Social Security Rules both sit under frcp.
• Amendments arrive on a fixed calendar. Under the Rules Enabling Act, an approved amendment is transmitted to Congress by May 1 and takes effect no earlier than the following December 1, the date the Court's orders use, unless Congress acts. Few other bodies of federal law change on a schedule this regular.
• That calendar is why monthly is the right cadence, not a weak one. A daily poll against an annually-changing corpus spends requests to learn nothing.
• Committee notes are load-bearing. Courts read them to decide what a rule means. Each API result carries the official publisher's source URL so you can pull the note from the authoritative copy.
• Local court rules are a separate corpus. FEDERAL_LOCAL_RULES holds circuit rules and the local rules of 32 district courts. Standing orders and judges' individual practices are in neither corpus.

Another installment in our US primary law corpus series, which covers the corpus one source at a time.

The state-level counterpart is State Court Rules API: 56 Jurisdictions and How to Query Them. For the other two small federal corpora that carry outsized weight in litigation, see US Sentencing Guidelines API: Querying the Manual That Sets Federal Exposure and State Constitutions API: 53 Jurisdictions With Article and Section Structure.

A short history: from 1789 to one set of rules

For a century and a half, federal courts mostly followed the procedures of the states where they sat. The Federal Judicial Center's history of the FRCP puts the consequence bluntly: "civil procedure differed from one federal court to another." It says the Rules Enabling Act of 1934 "empowered the Supreme Court of the United States to make uniform procedural rules for civil actions in the U.S. district courts," and that the Court then appointed an advisory committee of lawyers, scholars and judges to draft them.

The Court ordered the rules adopted on December 20, 1937. Justice Louis Brandeis dissented without writing an explanation, and the FJC passes along a friend's account that he feared the rules "would be unduly rigid." They took effect on September 16, 1938. As adopted there were eighty-eight rules in ten titles, and Rule 2 recognized the merger of law and equity into a single form of civil action.

The way rules change today comes from the same Act. The federal courts' own summary of the rulemaking process says the Supreme Court "officially promulgates the revised rules by order before May 1, to take effect no earlier than December 1 of the same year unless Congress enacts legislation to reject, modify, or defer the pending rules." That's the calendar this post is built around, and you can see it in the rules themselves. The amendment history line printed under FRCP 6 lists effective dates of Dec. 1, 1999, Dec. 1, 2001, Dec. 1, 2005, Dec. 1, 2007, Dec. 1, 2009, Dec. 1, 2016 and Dec. 1, 2023 (FRCP pamphlet, December 1, 2025 edition, uscourts.gov). The latest turnover so far took effect on Dec. 1, 2025: it amended Rules 16 and 26 and added Rule 16.1 on multidistrict litigation, according to the same pamphlet.

A tiny corpus with an outsized blast radius

1,130 sections is nothing next to 222,311 sections of CFR or 60,494 of US Code. It is also the corpus a litigation product hits on nearly every workflow.

Compute a response deadline, and you are in Rule 6 of the FRCP. Flag an objection in a deposition transcript, and you are in the FRE. Check whether an appeal is timely, and you are in the FRAP. Decide whether a claim survives a motion, and you are in Rule 12. None of that reaches for a statute.

The mismatch between size and usage is the reason to treat it as its own corpus with its own filter, rather than a folder inside a general federal blob. A 1,130-section corpus that you can scope precisely beats a 600,000-section one you have to sift.

The six rule sets and their source codes

The Supplemental Rules for Certain Admiralty or Maritime Claims and Asset Forfeiture Actions ride along with the civil rules under frcp, and they are included in the corpus.

Why 1,130 and not about 600. Every set except the Supreme Court Rules is held twice. The source codes above select the printing the courts publish, which held 589 sections on 12 October 2026 (the Supreme Court Rules, 48 sections, among them). The copy printed in the appendix to the relevant title of the US Code (Title 28 for the civil, appellate and evidence rules, Title 18 for the criminal rules, Title 11 for the bankruptcy rules) carries no source code and is selected with a code value such as uscapp_t28a_frcp; it held the other 541. On the same day code=frcp and code=uscapp_t28a_frcp each counted 98 sections, and code=sct counted 48.

The amendment mechanism, which is the useful part

If you build on this corpus, the single most valuable thing to understand is how these rules change. It is nothing like how statutes change.

Federal rules are amended through the Rules Enabling Act process, 28 U.S.C. 2071 through 2077. The path is fixed:

Each rule set has its own advisory committee. A proposed amendment is published for public comment, revised, and passed up to the Standing Committee, then to the Judicial Conference, then to the Supreme Court. If the Court approves, it transmits the amendment to Congress by May 1 under 28 U.S.C. 2074. Under that section the amendment takes effect no earlier than the following December 1, and December 1 is the date the Court's orders use, unless Congress passes a law to say otherwise.

One carve-out matters if you work with evidence rules. Section 2074(b) says a rule that creates, abolishes, or modifies an evidentiary privilege has no force or effect unless approved by Act of Congress, so a privilege change, in practice an amendment to the Federal Rules of Evidence, doesn't take effect on the default timetable. That is the exception people forget.

Why December 1 makes this corpus predictable

Statutes change whenever a legislature feels like it. Fifty state legislatures on fifty calendars, plus Congress, plus emergency sessions. There is no date you can point to.

Federal rules have one. The change surface for frcp, frcrp, fre, frap, and frbp collapses to a single annual turnover on December 1, with the content of that turnover public and readable from the previous May. Between December 2 and the following May 1, the national rules are almost certainly identical to what you cached.

That is why monthly is the correct refresh cadence rather than a compromise. Consider the three options:

The Supreme Court Rules (sct) are the one set that doesn't follow the Rules Enabling Act track. The Court amends its own rules by order on its own schedule, which is another argument for a monthly floor rather than an annual one.

You can audit the cadence instead of trusting it. GET /boards carries no charge and enumerates the watchable sources, each with its declared cadence and a lastRetrievedAt timestamp. If a board claims monthly and hasn't been retrieved since spring, that is visible before it becomes a support ticket.

A quick story: the day deadlines got simpler

If you want to know why this corpus is worth tracking, look at the 2009 change to Rule 6. Before it, a period of 11 days or more was computed differently from a shorter one. The committee note explains: "Intermediate Saturdays, Sundays, and legal holidays were included in computing the longer periods, but excluded in computing the shorter periods." The committee said the old rule "led to counterintuitive results." For example, "a 10-day period and a 14-day period that started on the same day usually ended on the same day," and the 10-day period "not infrequently ended later than the 14-day period."

The fix took effect December 1, 2009. Under the new Rule 6(a)(1), all deadlines stated in days are computed the same way. The trigger day isn't counted, every other day is counted, and a deadline that ends on a weekend or legal holiday moves to the next day that isn't one. A deadline calculator built before that date and never updated would have been wrong in a very specific way, and nobody would have noticed until a filing was late. All of this comes from the Advisory Committee's 2009 note to the rule.

Committee notes, and why they decide arguments

Every federal rule ships with Advisory Committee Notes, written by the committee that drafted the amendment. They explain what problem the change was meant to fix, what the drafters intended a phrase to mean, and often what they deliberately chose not to do.

Federal courts read them. When a rule's text is ambiguous, the committee note is the first place a judge looks, and briefs cite notes routinely. They aren't binding the way the rule text is binding, but they are the closest thing the rules have to legislative history, and they are far better organized than most legislative history.

A short example of how much a small amendment can carry: Rule 1 of the civil rules says the rules "should be construed, administered, and employed by the court and the parties to secure the just, speedy, and inexpensive determination of every action and proceeding." The 2015 amendment (effective December 1, 2015) is the reason the parties are in that sentence. The committee note says it was made "to emphasize that just as the court should construe and administer these rules to secure the just, speedy, and inexpensive determination of every action, so the parties share the responsibility to employ the rules in the same way," and adds that it "does not create a new or independent source of sanctions" (FRCP 1 and its notes). The note tells you what the change was meant to do, and, just as usefully, what it wasn't.

For a developer, that has one practical consequence: rule text alone can be misleading. A rule that reads as a bright line often has a note explaining the exception the committee assumed everyone understood. Every result this API returns carries the official publisher's own source URL for that rule, so when a note matters, pull it from the authoritative copy rather than inferring intent from the text.

Worked queries

Base URL is https://api.vaquill.ai/api/v1. Auth is Authorization: Bearer vq_key_.... Search costs 4 credits. Coverage and boards are free. A request that fails validation (a 422) isn't charged.

1. Pull FRCP 26 by citation

The discovery rule is probably the single most-hit rule in civil litigation software. Start from the citation, not from an id you guessed.

curl -X POST https://api.vaquill.ai/api/v1/us/statutes/search \
  -H "Authorization: Bearer $VAQUILL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "query": "Fed. R. Civ. P. 26 duty to disclose scope of discovery",
    "corpusType": "FEDERAL_RULES",
    "source": "frcp",
    "limit": 5
  }'

Take the actId off the top hit, then fetch the full text:

curl "https://api.vaquill.ai/api/v1/us/statutes/section/{actId}/body" \
  -H "Authorization: Bearer $VAQUILL_API_KEY"

On 12 October 2026 this query returned Rule 26 first, then Rules 37, 34, 33 and 16. Each record is a whole rule. /section/{actId} returns the record with its metadata and the publisher source URL. /section/{actId}/body returns the text. There is also a citation-resolve endpoint if you are starting from a properly formatted cite string rather than a natural-language query.

2. Phrase-match a defined term in the Rules of Evidence

Evidence work is exact-wording work. matchType: "phrase" is the setting you want.

curl -X POST https://api.vaquill.ai/api/v1/us/statutes/search \
  -H "Authorization: Bearer $VAQUILL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "query": "excited utterance",
    "corpusType": "FEDERAL_RULES",
    "source": "fre",
    "matchType": "phrase",
    "limit": 10
  }'

On 12 October 2026 that returned one record, Fed. R. Evid. 803, the rule that lists the hearsay exceptions, excited utterance among them. Nothing came back from bankruptcy or appellate procedure. Because each record is a whole rule, a phrase that sits inside a rule returns that rule. matchType takes any, all, or phrase. The default, any, is a hybrid of meaning and keyword matching, and phrase requires the exact phrase.

3. Scope to the Supreme Court Rules

curl -X POST https://api.vaquill.ai/api/v1/us/statutes/search \
  -H "Authorization: Bearer $VAQUILL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "query": "considerations governing review on certiorari",
    "corpusType": "FEDERAL_RULES",
    "source": "sct",
    "limit": 10
  }'

Supreme Court Rule 10 is the certworthiness rule and Rule 13 sets the time to petition, and both are questions an appellate product gets asked constantly. On 12 October 2026 this query returned Rules 10, 13, 14, 12 and 11 in that order. Scoping to source=sct keeps a certiorari question out of the district-court rules.

Paging is cut from a single ranking, so results never repeat or go missing between pages and a later page costs no more than the first. limit maxes at 50 and offset at 70, per the pagination rules.

What developers say

Software people keep noticing that the procedural rules look like code. In January 2015, a Hacker News commenter named rayiner wrote that "the FRE and the FRCP are really amenable to the sort of system analysis that comes naturally to engineers." His example was removal from state to federal court: a defendant files a notice of removal and the case moves at once, and if the plaintiff objects, a motion to remand sorts it out afterward. In his words, "this is exactly what a CPU does when it predicts a taken branch, starting execution of the branch target before resolving the branch condition" (Hacker News, January 2015). It's one commenter's analogy, but it explains why a lot of litigation tooling feels like state machines.

The less glamorous half is local practice. Another commenter, throwawaycities, put it plainly in May 2025: "All courts have local rules or even standing orders governing filings and pleadings" (Hacker News, May 2025). That matches the gap described below, and it's the part of federal procedure that a national rules database can't answer for you.

What is not in this corpus, and where the neighbours live

Local court rules are a separate corpus. Each federal district court issues its own local rules under Rule 83 of the FRCP, and those govern page limits, meet-and-confer requirements, chambers copies, and much of what actually gets a filing rejected. They aren't in FEDERAL_RULES. They are in corpusType=FEDERAL_LOCAL_RULES, which holds circuit rules and the local rules of 32 district courts (6,234 sections across 52 courts, which the coverage guide counts as 112 rule sets, because a court's civil and criminal rules are separate). A query for page limits on 12 October 2026 returned local rules from the Northern District of Illinois, the Northern District of Texas, the Middle District of Georgia, the Northern District of California, the Southern and Eastern Districts of New York (joint rules), and the Tenth and Federal Circuits. A district outside those 32 is not covered, so check that court's own site.

Standing orders and individual judges' practices are in neither corpus. Many judges publish their own requirements on top of the local rules. These are the least standardized documents in federal practice.

State court rules are a separate corpus. They live under corpusType=STATE_RULES, with more than 74,000 sections across 56 jurisdictions. State Court Rules API: 56 Jurisdictions and How to Query Them is the longer treatment of that corpus.

Change detection, and the honest limit

For monitoring, the corpus exposes change events captured at each refresh, per-section diffs on watched boards, and watch subscriptions with delivery logs. GET /boards lists what is watchable. Watches can be created, updated, listed, tested, and deleted, and you can pull a diff for a specific change, all covered in the alerts guide.

Point-in-time retrieval is a reconstruction. Each citation resolves to the stored text in force by default, and asOf=2019-12-01 on the body endpoint rebuilds the rule as it read before a given amendment cycle from the changes we observed after that date. The asOf block carries isBounded when the answer rests on when capture began, and a section we know changed but cannot rebuild comes back unavailable. There is also amendment history, a lastAmendedYear per section, a yearFrom and yearTo currency filter, and change events. Amendment History and Point-in-Time Law: What a Legal API Can and Cannot Tell You is the longer treatment.

A rules corpus has one sharp edge worth naming. If your product needs to show a litigator the version of Rule 26 that governed a case filed in 2018, test asOf on that rule early, read the isBounded flag before relying on the answer, and confirm it against the official committee archive.

Where this sits in the wider corpus

FEDERAL_RULES is one of the federal corpus types in a US primary law corpus totaling more than 5.3 million distinct sections, indexed as more than 20 million retrieval passages, with state codes for 56 jurisdictions. The federal side runs from the CFR at 222,311 sections and the Federal Register at more than 196,000 down through the US Code at 60,494, the Sentencing Guidelines at 1,281 including former versions, and the US Constitution at 74.

The collection layer is published at github.com/Vaquill-AI/open-us-law, including parsers and scrapers. The same API surface is also published as an MCP server at mcp.vaquill.ai, so an agent can query the rules directly. Our MCP guide covers that path.

FAQ

What are the Federal Rules of Procedure?

They are the national rules that govern how federal cases are conducted: the Federal Rules of Civil Procedure, Criminal Procedure, Evidence, Appellate Procedure, and Bankruptcy Procedure. They are primary law, adopted through the Rules Enabling Act process rather than passed as ordinary statutes. The Rules of the Supreme Court sit alongside them and govern practice before that Court.

How do the federal rules get amended?

An advisory committee drafts a change, publishes it for public comment, and sends it to the Standing Committee on Rules of Practice and Procedure, then to the Judicial Conference, then to the Supreme Court. If the Court approves, it transmits the amendment to Congress by May 1 under 28 U.S.C. 2074. It takes effect no earlier than the following December 1, the date the Court's orders use, unless Congress acts.

When do federal rule changes take effect?

December 1 of the year the amendment was transmitted (the statute sets that as the earliest date, and the Court's orders use it), unless Congress rejects, modifies, or defers it by statute. The one significant exception is a rule that creates, abolishes, or modifies an evidentiary privilege, which under 28 U.S.C. 2074(b) needs approval by Act of Congress.

Are Advisory Committee Notes binding?

No. The rule text is what binds. The notes are the drafting committee's explanation of what an amendment was meant to do, and courts cite them heavily when a rule's meaning is contested. Treat them the way you would treat well-organized legislative history: persuasive, frequently decisive, never the rule itself.

Does this API include local district court rules?

Not in FEDERAL_RULES. Local rules issued under FRCP 83 are in the separate FEDERAL_LOCAL_RULES corpus, which covers circuit rules and 32 district courts. Standing orders and individual judges' practices are in neither corpus, so if your workflow depends on a judge's chambers requirements, plan for a separate source.

How do I filter to just the Federal Rules of Evidence?

Set corpusType to FEDERAL_RULES and source to fre on a search call. The other codes are frcp, frcrp, frap, frbp, and sct. An invalid code returns a 422 whose message lists the valid source values, which cover every corpus that has named sources, not only the rules.

Can I get a rule as it read before a past amendment?

Yes, as a reconstruction. A citation resolves to the stored text in force, and asOf=YYYY-MM-DD on the body endpoint rebuilds an earlier rule from the changes observed after your date. Check isBounded and the engine in the asOf block before relying on it, because a section we know changed but cannot rebuild comes back unavailable. Amendment history, a currency filter, and change events per refresh sit beside it.

Why refresh a rules corpus monthly instead of daily?

Because the change surface is annual and dated. National rule amendments land on December 1 and are public from the previous May, so a daily crawl learns nothing on almost every day of the year. Monthly catches the turnover well inside any window where a user would act on it, and still picks up an off-cycle Supreme Court Rules order within weeks.

What does a federal rules search cost?

A search call is 4 credits. Coverage and boards are free. A request that fails validation isn't charged, and paging is cut from one ranking, so a later page costs the same as the first.

Priyansh Khodiyar

Co-Founder & CTO

Priyansh leads engineering and AI at Vaquill AI: the pipelines that pull statutes, regulations and court rules from every US jurisdiction's official publisher, and the REST API, MCP server and open dataset that serve them.