Brief citation checkers compared - Quick Check, Brief Analysis, Brief Analyzer, BriefCatch and LegiMatch
By LegiMatch Research Team · Published October 17, 2026 · Updated October 21, 2026 · 5 min read
Short answer: if you already pay for Westlaw, Lexis+ or Bloomberg Law, the brief tool included in it - Quick Check, Brief Analysis or Brief Analyzer - uses that platform's citator. If you don't, the choice is between a Word-based checker such as BriefCatch's RealityCheck and a research tool with a built-in brief check such as LegiMatch, which checks every case citation against the stored court opinion and, in its published blind tests, caught 98.6% of planted citation mistakes while calling none of 5,185 real citations fake. None of the other tools publishes an accuracy rate. Whatever you use, read the authorities you rely on.
At a glance
| Tool | Comes with | What it checks (per the vendor's descriptions) | Extras | Price |
|---|---|---|---|---|
| Westlaw Quick Check | Westlaw | KeyCite warnings on cited authority; quotation analysis | Suggests authority you didn't cite; table of authorities; can analyse an opponent's brief | Part of Westlaw subscriptions (Westlaw Advantage from $256.75/month online) |
| Lexis+ Brief Analysis | Lexis+ | Shepard's analysis of cited cases; Quote Check, including pin cites; flags unverified cites | Recommended authority; similar briefs | Part of Lexis+ subscriptions (quoted) |
| Bloomberg Law Brief Analyzer | Bloomberg Law | Flags cited authorities and whether they remain good law | Suggested cases, similar briefs | Included for Bloomberg Law subscribers (quoted) |
| BriefCatch RealityCheck | Standalone, in Microsoft Word | Whether cases and federal statutes exist; quotations against the source; pin cites | Editing suggestions for legal writing | From $60 per seat a month (billed annually); 7-day trial |
| LegiMatch Brief Check | LegiMatch | Every case citation against the stored opinion: existence, case name, year, court, pin cites, quotations, later negative treatment; statute sections, including whether a section fits the sentence it supports | "Did you mean" corrections, side-by-side quote view, cases you may have missed, table of authorities (PDF/Word), Word add-in, fact-based case search | Unlimited on every plan, from $99/month; 14-day free trial, email only |
Vendor features change often; confirm current details with each vendor before buying.
Which ones publish how accurate they are
| Tool | Published accuracy for citation checking |
|---|---|
| Westlaw Quick Check | None found |
| Lexis+ Brief Analysis | None found |
| Bloomberg Law Brief Analyzer | None found |
| BriefCatch RealityCheck | None found |
| LegiMatch Brief Check | Yes - 21 blind test rounds on 1,635 real documents; latest rounds: 1,397 of 1,417 planted mistakes caught (98.6%), 190 of 190 wrong pin pages caught, 0 of 5,185 real citations called nonexistent. Full method and results |
How to choose
You already have Westlaw, Lexis+ or Bloomberg Law
Use the tool you have. Quick Check, Brief Analysis and Brief Analyzer run on their platform's editorial citator (KeyCite, Shepard's or BCite), which no independent tool fully replicates.
You're a solo or small firm without a big-platform subscription
Look for three things:
- Checks against the actual opinion, not a chatbot's memory - existence, name, pin cite and quotation.
- Good-law signals for the cases you rely on.
- A known accuracy and a price you'll keep paying, without a multi-year contract.
LegiMatch was built for this: Brief Check is unlimited on every plan with no annual contract, and the same subscription covers fact-based case search, quotation search, statutes and alerts. Its good-law flags come from later decisions in its own database; they are not a full replacement for KeyCite or Shepard's, so for a high-stakes filing confirm key authorities in a citator too.
You mainly want help inside Word
BriefCatch works inside Word and also edits your writing. LegiMatch has a Word add-in too: it checks the open document, jumps to each problem and replaces a wrong citation with the suggested one.
You only need to catch invented citations occasionally
LegiMatch's free citation checker, with no sign-up, confirms whether case citations match real opinions. It doesn't replace a full pre-filing review.
What every brief check should catch
| Problem | Example |
|---|---|
| Citation to a case that doesn't exist | An AI-invented case with a realistic-looking cite |
| Real citation, wrong case name | The most common sign of an AI-invented citation |
| Pin cite outside the opinion | A pinpoint page beyond the opinion's last page |
| Misquotation | Quoted words that don't appear in the opinion |
| Bad law | A case later reversed or overruled |
| Wrong statute section | A real section cited for a point it isn't about |
See how to check a brief for fake citations before you file for a step-by-step routine, by hand or with a tool.
Frequently asked questions
What is the best brief citation checker?
If you subscribe to Westlaw, Lexis+ or Bloomberg Law, the brief tool included in it, because it uses that platform's citator. For small firms without one, choose a tool that checks each citation against the actual opinion text and tells you how accurate it is - such as LegiMatch Brief Check, which publishes its blind-test results and is unlimited on every plan from $99 a month.
Is there a cheaper alternative to Westlaw Quick Check?
Yes. Independent tools check brief citations without a Westlaw subscription. LegiMatch Brief Check is unlimited on every LegiMatch plan, starting at $99 a month with no annual contract, and in the 14-day free trial. Its good-law flags are not a full KeyCite replacement.
Is there a free AI hallucination checker for legal briefs?
Yes, with limits. LegiMatch has a free citation checker with no sign-up that confirms whether case citations match real opinions. Full brief checks with pin cites, quotations, statutes and a table of authorities usually require a paid plan or trial.
Do brief checkers replace reading the cases?
No. They catch citation errors and flag treatment, but they can't tell you whether a case actually supports your argument. You remain responsible for reading the authorities you cite.
Sources
- Thomson Reuters, "Quick Check" (Westlaw product page); Westlaw Advantage plans and pricing
- LexisNexis, "Brief Analysis" feature spotlight (Lexis+)
- Bloomberg Law, "Bloomberg Law Introduces Brief Analyzer"
- BriefCatch, RealityCheck and pricing pages (checked 20 October 2026)
- LegiMatch, blind test of Brief Check
This article is general information about legal research, not legal advice. Verify every authority before relying on it.
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