Catch fabricated legal citations before you file.
A Microsoft Word add-in that scans every citation in your brief and flags the ones that don't exist. Built for lawyers who use AI to draft, and don't want to be the next Avianca.
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What Proof Brief does
- Verifies every citation against CourtListener. Real cases get a green checkmark; cases that don't exist in any indexed reporter get flagged red.
- Underlines flagged citations directly in Word. No copy-paste, no separate window — wavy underlines appear inline as you read.
- Distinguishes "doesn't exist" from "not in our index". An honest amber state for citations CourtListener can't confirm, with a dual-reading caveat — never a false-negative on a real case.
- Handles statutes, regulations, court rules, and constitutional cites locally. No false-positives on USC, CFR, FRCP, or US Const just because they're not "cases".
- Corroborates Westlaw and LEXIS proprietary cites against the open record by case name + court + date when CourtListener doesn't return a direct hit.
Why it exists
In June 2023, two New York attorneys cited six fabricated cases from ChatGPT in a brief filed in Mata v. Avianca. The judge issued sanctions and a public reprimand. Since then, similar incidents have surfaced in California, Colorado, and federal courts.
The pattern keeps repeating because the existing tools (Westlaw, LEXIS, Bluebook checkers) ask "is this citation formatted correctly?" — not "does this case actually exist?" Proof Brief asks the second question.
How it works
- Install the add-in in Word (sideload via manifest).
- Click "Scan citations" on the home tab.
- Read the cards in the side pane. Click any to scroll directly to the citation in your document.