Syfert Legal Research
Verify legal citations, case treatment, quotes and whole briefs against 10.7M U.S.
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Verify legal citations, case treatment, quotes and whole briefs against 10.7M U.S. opinions
Server tool list (13)
Raw names from tools/list. Only developers need these.
| search_cases | Full-text search over 10.7M 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. 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 backend that served the search: pro = the dedicated index, free/anon = the cloud index behind a short queue. |
| get_case | Fetch one case: metadata, parallel citations, treatment flag, and full opinion text (paginated via offset/max_chars). Identify the case by cluster_id (from search_cases results) or by reporter citation. |
| check_citation | Verify a legal citation actually exists before using it. CASES: returns the real case at that citation, its treatment flag, and (if expected_case_name given) whether the name matches. This catches hallucinated or miscopied citations. Local misses are automatically re-checked LIVE against CourtListener, so very recent cases are distinguished from fabrications. 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. |
| get_treatment | 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 Returns the Syfertize treatment flag (red = overruled/superseded, yellow = questioned/distinguished, green = followed, procedural = cert/rehearing denied) plus the citing cases behind each signal with quoted context. |
| check_brief | 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 quoted passages against passages courts have actually quoted from each case (misquote signal: verify flagged quotes with get_case), 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. |
| get_propositions | 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. |
| get_citing_cases | 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). |
| find_related_cases | 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. If the case has no family, fall back to get_citing_cases or search_cases. |
| find_court | 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. |
| search_quotes | 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. |
| find_issues | 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. |
| search_statutes | 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"). |
| get_statute | Fetch the full current text of a statute, rule, or code section. |