Skill v1.0.0

version: "1.0.0" name: cite-check description: A procedure for auditing every legal citation in a brief, memo, motion, or opinion letter against the CourtListener database — hallucination detection for legal writing. Use when asked to cite-check, verify citations, validate authorities, confirm cases are real, or review a draft before filing or sending.

Fabricated and mischaracterized citations are the signature failure of AI-assisted legal writing, and courts sanction filers for them. Treat every citation in the document as unverified until a database lookup confirms it. Never mark a citation verified from memory — verification means a live lookup returned the case.

<procedure>

1. Extract every citation. Read the full document and list each legal

authority it cites: case citations (full and short-form, including id. and supra references resolved back to their antecedent), statutes, regulations, and rules. For each, record the exact anchor where it appears as [<Document> § <section>] and the proposition the document uses it for (quote the sentence it supports).

1. Verify each case against CourtListener. Use the CourtListener MCP

server when available; otherwise use the case-law tool. Search by case name and by reporter citation. Both sources cover U.S. opinions only — for non-U.S. authorities, and for statutes and regulations, do not guess: classify them as unverifiable here and list them for manual confirmation.

1. Compare the holding. For each case found, read the returned snippet and

metadata. Confirm the case stands for the proposition the document cites it for — a real case cited for something it does not say is as dangerous as a fake one. Check the cited court and year against the database record.

1. Classify each citation into exactly one status:

• verified — the case exists, the reporter citation, court, and year

match, and the retrieved content is consistent with the cited proposition.

• not found — no matching case by name or citation; presumptively

fabricated until the author produces the source.

• ambiguous — a case by that name exists but the citation, court, year,

or party names do not match, or multiple candidates exist, or the source could not verify it (non-U.S. authority, statute, regulation).

• supports-different-proposition — the case is real but the retrieved

content does not support, or contradicts, the proposition cited.

1. Output a findings table with one row per citation:

The Evidence column carries the CourtListener URL and matched citation for verified entries, and the specific mismatch for everything else. </procedure>

Close with a summary count by status and a clear verdict: a document is safe to file or send only when every citation is verified or independently confirmed by the supervising attorney. Never soften a not found into "likely correct" — report it as unverified and stop there. Do not invent a replacement citation for a bad one; flag it and let counsel decide.