Syfert Legal Research

Full-text search over 10.8M U.S. court opinions (all states + federal, via syfert.com). Call this to find case law on a topic, locate a case by name, or find cases citing a statute. Routing: a proposition or quoted language -> find_authority (pasted verbatim); a doctrine name or fact pattern -> find_issues; a party name, statute number or keywords -> search_cases. Each hit carries bluebook and url (snippet up to 240 chars); a hit whose snippet quotes an earlier case carries passage_origin, the case to cite for that language. A q that is one citation or an "X v. Y" caption naming one case decisively also returns that case as direct_hit above the results (find_case does only that lookup). Query syntax: boolean AND/OR/NOT, "exact phrases", proximity (term1 w/5 term2), wildcards (neglig*), and field filters inside q (name:, judge:, syllabus:). Statute-style numbers like 83.49 are matched as citations to that statute. total may be null: a court or date filter makes the exact count too expensive to compute, and total_pages + total_note then carry the scale. partial: true means the time budget was hit; see partial_note. tier names the caller's plan; _source names the backend that served the search: xeric = the dedicated index, cloud = the cloud index behind a short queue. When no opinion holds every word of a long query, the answer may carry relaxed=true with relaxed_note and relaxed_terms_kept / relaxed_terms_dropped: its rows (closest_match) hold only the kept words. A q that is an "X v. Y" caption also lists, first on page 1, the decisions whose caption carries both parties (abbreviations and agency acronyms read: "Stone v. INS", "ANR Pipeline Co. v. FERC"), marked matched_by caption; the ranked rows follow unchanged. semantic: true ranks opinions by MEANING instead of words (a paraphrased fact pattern finds cases that share none of its words; rows carry similarity, no snippet; state, court, date and status=published filters apply); a text search with no hits is retried

Fast direct lookup: give a citation or a case caption and get THE case (or 'not decisive' with up to 5 candidates) without a full-text search. Use search_cases for topics and words. A citation ("384 U.S. 436", "Miranda v. Arizona, 384 U.S. 436, 444 (1966)", "449 F. App'x 901", "2019-Ohio-10") resolves through the reporter index; when a case name is given (in the query or as expected_case_name) and the case at that citation carries a different name, the answer is NOT decisive (problem name_mismatch) and names the case that is really there. A caption ("Miranda v. Arizona", or one distinctive name such as "Celotex") is decisive when the top match is at least twice as strong as the runner-up, or when the case name IS the caption word for word (punctuation, company suffixes and abbreviations read) for one decision in the corpus (several filings of one decision count once: the answer is the Published, reported record, the others listed in also_filed_as) -- an exact caption outranks any opinion-text match; common captions ("Smith v. Jones", "State v. Johnson") are not decisive by design. A docket number ("2D09-5223", "No. 1:15-cv-00001" with court, "17-1618") resolves through the docket index: decisive when one case carries it, otherwise problem ambiguous_docket with the candidates (a Supreme Court number also matches its cert-stage entries). The answer carries case (bluebook, url, link_md, treatment_flag), kind (citation|caption|docket), decisive, candidates, and a note when not decisive. A red, yellow or procedural case also carries treatment_flag_reason and treatment_flag_basis. A Westlaw / Lexis number whose sources disagree about the case carries database_caution. For a caption that is not decisive, the candidates whose caption carries both parties (abbreviations and acronyms read) are listed first, marked matched_by caption, with caption_matches = how many decisions carry it. A misspelt or partial caption that nothing matches ("Palsgraph v. Long Island R.R.", "City o

Fetch one case: metadata, parallel citations, treatment flag, and full opinion text (paginated via offset/max_chars). cited_by is CourtListener's citation count; for a decision filed as several twin clusters it is summed over them (cited_by_note says so), and a duplicate or stub twin id is answered with its survivor (note says so). Citations inside the returned text are checked against the reporter index (embedded_citations); citation_warnings names any the court itself got wrong. Identify the case by cluster_id (from search_cases results) or by reporter citation. find_text returns passages: up to 5 sentence-bounded windows holding a phrase (or its closest match) with star_page and offset, so a long opinion need not be paged (pass include_text=false to get only those); quotable=true adds quotable_passages, the passages of this opinion other courts quote. Quotation marks mean pasted from a tool result (opinion text, passage, best_match). If you typed a quote from memory, run verify_quote and use best_match. Run check_brief on the finished draft and apply its corrections. Copy cite_as for the citation (first page, then pin). A California Court of Appeal opinion with a Supreme Court docket event carries citability {status depublished | review_granted | transferred | review_decided, date, s_number, source, rule Cal. R. Ct. 8.1115}; depublished / review granted / transferred lead with status_warning (a depublished opinion may not be cited; one under review has no binding effect, is citable for persuasive value and to establish a conflict in authority, and the cite must note the grant; one transferred with directions to vacate is generally not citable; order_says quotes the order when held); old_rule true = review granted before 2016-07-01, when the grant itself depublished the opinion (a later decision did not restore it): may_cite no, check the docket. focus = a question or proposition in plain words (no brief sentence needed): returns focus_passages, the 4 (focus_n, at

Verify a legal citation actually exists before using it. CASES: returns the real case at that citation, its treatment flag, and whether the name matches: expected_case_name, or else a case name written in the citation itself ("Roe v. Wade, 410 U.S. 113"). This catches hallucinated or miscopied citations. A reporter cite that is not indexed comes back with a verdict, and the verdict is what to act on (MCP13_20260925): exists_unindexed = the case is REAL (a court in the corpus prints this exact citation, see cited_by_corpus, or the case is found by name and year, see name_candidates) and only our reporter index lacks it -- never call it a hallucination; not_indexed = no evidence either way, read volume_coverage: for 2019+ volumes of the state regional reporters we often index under 30% of the cases (coverage_pct), so a miss there is weak evidence; interior_mismatch / strong = the page provably sits inside a differently named case, or the volume is complete and nothing turns up by name -- treat as likely fabricated; name_mismatch = opinions in the corpus print this citation for a DIFFERENTLY named case (cited_by_corpus.examples[].printed_as): the cite is real but not the case you named -- fix the name or the cite. Local misses are also re-checked LIVE against CourtListener. STATUTES, REGULATIONS AND COURT RULES: a citation that is not a reporter cite is checked against the corpus that holds it (50 states + DC, 44 states' court rules, the Florida Administrative Code, USC/CFR/federal rules/USSG) and comes back with type, verified, the canonical citation, title, url and link_md; verified=false carries nearby sections and a coverage note, and is NEVER proof the section does not exist. ALWAYS use this to verify any citation that will appear in a legal document. With quote, the quoted words are checked against the opinion the cite resolves to (quote_check, the verify_quote block). PROPOSITION-LEVEL TREATMENT (MCP14_20260925): pass proposition (what you cite the case for; quo

Check one quotation against the full text of the opinion it is attributed to, before it goes in quotation marks. Returns verdict (verbatim | near | absent), percent, best_match (the opinion's own sentence, up to ~600 characters), star_page (the last *page marker before it, null when the text carries none), offset (get_case offset), case and advice. near means the opinion says it in other words: paste matched_span (the opinion's words over the span you quoted) instead; best_match is the sentence around it. absent means the words are not in this opinion. Identify the case by cluster_id or reporter citation (case_name helps a citation newer than the reporter index). Quotation marks mean pasted from a tool result (opinion text, passage, best_match). If you typed a quote from memory, run verify_quote and use best_match. Run check_brief on the finished draft and apply its corrections. Copy cite_as for the citation (first page, then pin). A case_name alone also works: find_case decides, and a name that is not decisive returns candidates instead of an answer.

Is this case still good law? Returns the Syfertize treatment flag (red = overruled/superseded, yellow = questioned/distinguished, green = followed, procedural = cert/rehearing denied) plus the citing cases behind each signal with quoted context. A case can be green overall and red on the proposition you need it for (MCP14_20260925): propositions_summary lists the propositions courts cite it for (most-cited first), each with its OWN flag; pass proposition (your use of the case) and proposition_match returns the one that matches, with its negative_citers, and treatment.proposition_note states the result ("no proposition-level signal for this use" = only the case-level flag applies). A red, yellow or procedural flag also carries treatment.flag_reason (why it is flagged, in one line, as the case page shows it), treatment.flag_basis (overruled_by | subsequent_history | scope | citing_events | curation_pin | twin_carry | higher_court_limit | validated_annotations) and treatment.flag_evidence. compact=true returns only the flag, scope, overruled_by and the top negative citers (about 90% smaller). When the annotation verb (overruled_by.verb) and the scope's verb differ, flag_reason leads with the scope's and carries the other in parentheses (overruled_by.verb_note). A case_name alone also works: find_case decides, and a name that is not decisive returns candidates instead of an answer. A California Court of Appeal opinion with a Supreme Court docket event carries citability {status depublished | review_granted | transferred | review_decided, date, s_number, source, rule Cal. R. Ct. 8.1115}; depublished / review granted / transferred lead with status_warning (a depublished opinion may not be cited; one under review has no binding effect, is citable for persuasive value and to establish a conflict in authority, and the cite must note the grant; one transferred with directions to vacate is generally not citable; order_says quotes the order when held); old_rule true = review gr

Audit ALL citations in a draft brief, motion, or memo at once (wraps syfert.com Brief Check). Extracts every reporter citation, verifies each exists, checks the case name the document claims against the real case (hallucination detection), checks each quoted passage word for word against the cited opinion's own text (misquote = not in that opinion; unquoted_by_courts = the text could not be compared and no court has quoted those words from the case: check it with verify_quote), traces an unmatched quote to the case the language actually ORIGINATES in (quote_origin: attribute with "(quoting …)" or cite the source), and returns treatment flags with replacement suggestions for red-flagged authority. Also audits every STATUTE, REGULATION and COURT-RULE citation in the document against the corpus that holds it, reported separately under "statutes" (verified=false means not found in that corpus, which is not proof the section is wrong). ALWAYS run this on a finished draft before delivering it. Use mode=attack on an OPPONENT's brief to get ammunition: distinguishing and criticizing citers for each of their cites. Text over the size cap (128KB anonymous, 512KB with a token) is cut before the audit and the response then carries stats.truncated_bytes plus an INCOMPLETE AUDIT warning. corrections lists every quote the cited opinion does not carry verbatim, with replace_with (the opinion's own words, or, for verdict statute_text / statute_misquote / rule_text, the statute's or rule's own words; on verdict misattributed replace_with is null and cite_instead gives the citation) and star_page, and every unresolved or name-mismatched citation. Each unresolved citation carries verdict (exists_unindexed = a real case our index lacks, confirmed by a citing opinion or by name -- keep it; not_indexed = unknown, weigh volume_coverage (thin 2019+ volumes make a miss weak evidence); interior_mismatch/strong = likely fabricated), so do not report every unresolved cite as a hallucination (MC

What is this case actually cited FOR? Returns the distinct legal propositions courts cite the case for (headnote-grade), each with its OWN treatment flag and counts. A case can be good law on one proposition and overruled on another. Use before citing a case for a specific point, and to find the strongest proposition to cite it for. passage is the opinion's own wording of the proposition with its star_page; passage null means citing courts paraphrase it. Pass proposition (your use of the case) to get proposition_match, the one proposition it matches, and proposition_note (MCP14_20260925). Quotation marks mean pasted from a tool result (opinion text, passage, best_match). If you typed a quote from memory, run verify_quote and use best_match. Run check_brief on the finished draft and apply its corrections. Copy cite_as for the citation (first page, then pin).

Full citator list: every ranked case citing this one, with judge-written parentheticals (usable verbatim in a brief), verbatim quotes, pin cites, and the citing court's own Bluebook signal. Filter by flag color. Best for FINDING SUPPORTING AUTHORITY and parentheticals; for comprehensive negative-treatment checking use get_treatment (this list covers only each case's top-ranked ~50 citers).

Expand research from one good case: returns the doctrinal family it belongs to: the line of frequently co-cited cases around an anchor authority (curated set of ~1,500 major doctrinal lines; landmark cases only). Use when you have one on-point case and need the rest of the line. A case in no family gets its own most co-cited cases instead (related_source "co_citation"; MCP22_20260927).

Resolve a court name to court_id values usable in the search_cases court filter. Also resolves whole GROUPS of courts (tribal courts, veterans, bankruptcy, all U.S. district courts) to the single aggregate token that filters on all of them: see court_groups in the result. Each court row carries bluebook, the Bluebook court abbreviation for a citation parenthetical (e.g. "Fla. 1st DCA"; "U.S." for the U.S. Supreme Court, whose case citations to U.S. / S. Ct. carry no court in the parenthetical; absent for courts with none on file); citation_string is the stored CourtListener string.

Find every case that has quoted a phrase. Phrase-matched search over 4.3M distinct passages quoted by two or more opinions, ranked by how many cases quote them. Use it to (a) find the true source of half-remembered language BEFORE attributing it, and (b) locate the canonical wording of a rule. Returns the passage, its source case, and adoption counts. When no passage has the exact phrase it falls back to passages sharing its distinctive words (match_kind relaxed), and it adds the mined propositions later courts cite a case for (match_kind proposition). Same tool as find_authority. Routing: a proposition or quoted language -> find_authority (pasted verbatim); a doctrine name or fact pattern -> find_issues; a party name, statute number or keywords -> search_cases. Quotation marks mean pasted from a tool result (opinion text, passage, best_match). If you typed a quote from memory, run verify_quote and use best_match. Run check_brief on the finished draft and apply its corrections. Copy cite_as for the citation (first page, then pin). The first 3 rows carry star_page and cite_as.

Find the case to cite for a proposition. Paste the proposition or the language you need authority for VERBATIM; do not convert it to keywords. The result names the source case to cite (source_case), the verbatim passage, and how many courts have adopted it (quoted_by_cases); match_kind says how it matched: exact_phrase (the passage contains your words), relaxed (it shares your distinctive words), proposition (a rule later courts cite that case for). A miss means no court has quoted or been cited for that wording; try find_issues for the doctrine, or search_cases with 3-4 distinctive words. Routing: a proposition or quoted language -> find_authority (pasted verbatim); a doctrine name or fact pattern -> find_issues; a party name, statute number or keywords -> search_cases. Quotation marks mean pasted from a tool result (opinion text, passage, best_match). If you typed a quote from memory, run verify_quote and use best_match. Run check_brief on the finished draft and apply its corrections. Copy cite_as for the citation (first page, then pin). The first 3 rows carry star_page and cite_as. A quotation inside the proposition (in quotation marks) is also searched on its own: passages that contain it word for word come first, match_kind quotation (matched_quotation names it). It also finds, by meaning, the PAGES later courts cite for a paraphrased proposition (match_kind cited_for_label: pin page, cite_as with the pin, a generated label of what the page is cited for, how many courts cite it, and the treatment of those citations), and returns string_cite: those pages one per case in Bluebook order with "(cited for …)" parentheticals to rewrite from the opinion. Up to 3 semantic_case rows at the end are whole opinions closest in meaning to the proposition: leads to read, not quotations. Every row carries match_sentence (the passage sentence or label that matched) and closeness: verbatim | close | related, measured on wording and meaning (related = it shares the subject and ma

ENTRY BY ISSUE. Use this FIRST when the question arrives as facts or an issue rather than a case name ("can the appellate court affirm on a ground the trial court never reached", "impact rule emotional distress", "Fabre defendant"). Returns (1) the doctrine as courts in that STATE actually name it, with the cases on EACH side (followed_by / questioned_by, from how each citing opinion treated the case), example sentences judges wrote, the statutes those opinions construe, and every state where the phrase is alive with its year span (a doctrine retained in one state and abandoned elsewhere shows as a stalled span); and (2) the matching mined propositions (the rule text courts quote) with per-passage flags. Doctrine name is not case health: an issue can be alive while its anchor case is red. Read questioned_by before relying on followed_by. A q of more than 8 substantive words is read as a proposition: propositions (matched against all of it) come first. The default answer holds 3 issues and 5 statutes and stays under ~12,000 characters (issues_omitted counts the rest); max_issues or detail=true returns more. Routing: a proposition or quoted language -> find_authority (pasted verbatim); a doctrine name or fact pattern -> find_issues; a party name, statute number or keywords -> search_cases. Each issue also carries tree: where the doctrine sits in the Syfert issue tree (area > group > issue, built from what later courts cite pages for), how alive it is in the state, and related issues beside it. Browse the tree with node instead of q: find_issues(state="fl", node=0) lists the top areas cited by that state's courts; follow each child's next call down to an issue, which lists the pages courts cite for it.

Search statutes, COURT RULES and codes by citation or topic, for EVERY U.S. state plus federal. For a specific state, pass state="wi" (any two-letter code, all 50 states + DC) and a topic or section number; add kind="rule" for that state's court rules or kind="statute" for its code. Without state it searches only the kinds named in kinds (default: Florida). Handles citation lookups ("83.49", "174.02") and topic queries ("dog bite strict liability"). Each result carries currency (text_last_changed and, where recorded, last_amended_year / effective_date / status / successor) and corpus_currency gives each corpus's edition and current-through date. OPERATIVE DATE: statute text is the edition this corpus holds, not the law on every date. For a crime, a contract, a limitations period or a procedural step, establish the operative date first (offense, contract, accrual or filing date) and pass it as as_of (YYYY-MM-DD); say so when the text postdates the facts, since an older offense may be charged under a predecessor section. (as_of is taken by get_statute and check_citation.)

Fetch the full text of a statute, rule, or code section: the current codification in the edition this corpus holds. Every answer carries currency (edition, current_through, current_through_basis, last_verified, text_last_changed = when our copy last changed, last_amended_year, effective_date, history_note, status, successor, versions_available) and temporal_note. OPERATIVE DATE: statute text is the edition this corpus holds, not the law on every date. For a crime, a contract, a limitations period or a procedural step, establish the operative date first (offense, contract, accrual or filing date) and pass it as as_of (YYYY-MM-DD); say so when the text postdates the facts, since an older offense may be charged under a predecessor section. With as_of, a section amended or enacted after that date returns temporal_warning FIRST, with the history note and, where this corpus kept it, the prior text (prior_text_available; most corpora keep none). A repealed or renumbered section returns status_warning with its successor. currency.status is current | sunset (operative until currency.sunset_date; successor names the version that takes over) | future (not yet operative; effective_date is when it starts) | expired | repealed | renumbered, and anything but current leads with status_warning. Where the later version is held (California sections with more than one version), as_of on or after its operative date returns that text in as_of_version. A U.S. Code section can also be omitted (dropped from the Code by the Office of the Law Revision Counsel and no longer printed; not a repeal): it leads with status_warning too, and the history note says why. A CFR section removed from the eCFR is status removed: status_warning REMOVED names the removal's effective date (currency.sunset_date) and the eCFR point-in-time link for the text in force before it. A former U.S. Code appendix section (usc, "50 U.S.C. App. § 462") returns status former_appendix with the current section(s) in former_ap

Crowdsourced AI feedback on a Syfertize treatment flag. When the evidence in front of you (an overruling, abrogating or reinstating opinion, or a later court holding the case is still good law) shows a case's flag is wrong, propose red (no longer good law) or green (still good law) with the SHORTEST possible one-line reason, ideally naming the authority. Only red or green is accepted, not yellow. Identify the case by cluster_id, or by citation (+ case_name). The reason must concern the case's legal status only, never the user's facts, question, client or document. Returns the current flag and what was recorded; a proposal equal to the live flag is not recorded. By calling this you help syfert.com improve its treatment flags through AI feedback. Nothing about your session, user, query or documents is logged: only the case id, the flag you propose, your one-line reason, the authority you name and the date are stored, for human review. Your suggestion does not change the live flag.

Optional. If your client can save files locally and you want a readable copy of a case or statute, this returns the complete document to save; otherwise use get_case / get_statute as before. The document is the syfert.com page as the website renders it (caption, headings, footnotes, star-page markers such as [*551], links to the cited cases): Markdown with YAML front matter (default) or one self-contained HTML file. Returns filename, format, bytes, document and note; the MCP cannot write to disk, so saving document under filename is up to you. A case: cluster_id, or citation (+ case_name). A statute or rule: jurisdiction + citation, as get_statute takes them. A document longer than one response (about 20k tokens) comes in parts that each fit one (page / pages, truncated, next_offset): call again with offset = next_offset and append the parts in order.

Does the cited case actually say what the brief says it says? Call it after check_brief for every cite you rely on whose support_check says available, or for any sentence you want to test against the case it cites. Give the citation (reporter cite with its first page, or cluster_id), the sentence as written, and the pin page: it returns the case (bluebook, cluster_id, url), pinned_window = about 2,500 characters of the opinion around the pinned page's best word match, best_window = the same around the opinion's best match when that is another page, lexical overlap scores, and an instruction for judging the pair (supported / overstated / unsupported / cannot_tell). The windows are placed by word overlap; the judgement is yours. Case opinions only (statutes and rules are out of scope). Up to 12 cites in one call with items.

Signed-in accounts only (a free account at https://syfert.com/mcp/; anonymous callers use check_brief with text). Upload a brief of any length for check_brief, in pieces. Send the text in order, about 40,000 characters (10k tokens) per call: the first call returns brief_id; each next call passes brief_id and seq (2, 3, ...); the last passes final=true (a short brief can go in one call with final=true). Then call check_brief with brief_id. The text and its results are held in server RAM only, for your credential alone, and are deleted right after the last page of every section is read, after an hour idle, or by brief_delete.

Signed-in accounts only (a free account at https://syfert.com/mcp/; anonymous callers use check_brief with text). Read the results of check_brief(brief_id) one page at a time (each page under ~20k tokens). section: corrections (ranked by severity), cites (one full row per citation, as check_brief with detail="full"), quotes_unattached, statutes. Start without cursor, then pass next_cursor until it is null. After the last page of every section the session is deleted (session_deleted: true).

Signed-in accounts only (a free account at https://syfert.com/mcp/; anonymous callers use check_brief with text). Delete an uploaded brief and its results from the server now (they are otherwise deleted after the last page is read, or after an hour idle).