AI Citation Checking for Law Firms: FirmCited vs Churci, Ascero, and KeyCite (2026)

BizLegal AI Editorial Team · September 6, 2026 · 8 min read

AI Citation Checking for Law Firms: FirmCited vs Churci, Ascero, and KeyCite (2026)

AI-generated legal writing has created a new malpractice risk: fabricated citations. Courts have sanctioned attorneys for filing briefs with cases that do not exist — the Mata v. Avianca matter is the most widely reported example. This article compares the tools that check citations, honestly, so a firm can pick the right layer of protection.

Last updated: 2026-09-06 · 8 min read

Quick Answer

Citation-checking tools fall into four tiers: per-citation checkers (Churci, ~$10-$30 per batch), subscription verifiers (Ascero AI, $79/month or $29/document), traditional citators (KeyCite, Shepard's, BCite — included with Westlaw/Lexis/Bloomberg), and full-brief audits (FirmCited, $490 per audit). Per-citation tools catch fabricated cases cheaply. Citators tell you whether a real case is still good law. A full-brief audit does both across an entire filing — which is what a partner should want before a brief goes out the door.

The problem: two failure modes

AI citation errors come in two distinct flavors, and most tools only catch one:

1. Fabricated authority. The AI cites a case that does not exist, or a real case with a wrong name, wrong reporter, or wrong holding. This is the failure mode that gets lawyers sanctioned.
2. Misapplied authority. The case is real, but it does not actually support the proposition it is cited for — or it has been overruled, reversed, or limited since the brief was drafted.

A complete citation check needs to catch both. Traditional citators (KeyCite, Shepard's, BCite) are excellent at the second — they track the subsequent history of real cases. They cannot catch the first, because a fabricated case has no history to track. That gap is exactly what the new AI citation tools are built to close.

The comparison

| Tool | Pricing | What it checks | Best for | |---|---|---|---| | Churci | $9.99 / 50 checks, $29.99 / 200 | Case exists + supports the point; flags misquotes | Individual citations, solo and small firms | | Ascero AI | $79/mo unlimited or $29/doc | Extracts and verifies every citation in a draft | Firms with steady brief volume | | LexiCite360 | Contact | Deterministic matching, overruled-law detection | Firms that want AI-free verification | | CiteCheck | Contact | Citation + proposition + brief quality | Firms wanting deeper analysis | | KeyCite / Shepard's / BCite | Included in Westlaw / Lexis / Bloomberg | Whether a real case is still good law | Standard citator checks | | FirmCited | $490 per audit | Full-brief audit: existence, support, history, evidentiary-grade report | Firms needing a comprehensive pre-filing audit |

When each makes sense

Per-citation checkers (Churci and similar). The cheapest layer. If you have a handful of citations to verify — a memo, a short motion — a $10-$30 batch check is the right call. These tools are built for the solo practitioner and small firm.

Subscription verifiers (Ascero and similar). For firms that file briefs every week, a flat monthly or per-document price makes sense. You get extraction of every citation in a draft plus verification, at a price that scales with volume.

Traditional citators (KeyCite, Shepard's, BCite). You already pay for these inside Westlaw, Lexis, or Bloomberg. They are the right tool for the "is this case still good law" question — and they are the wrong tool for the "does this case exist" question. Use them, but do not assume they cover the AI-hallucination risk.

Full-brief audits (FirmCited). When a brief is about to be filed, the question is not "is this one citation good" but "is every citation in this filing good." A $490 audit covers the whole brief — existence, support, and history — and produces an evidentiary-grade report you can keep in the matter file. For a partner signing a brief, that is cheap insurance against a sanctions motion.

The FirmCited angle

FirmCited is built for the pre-filing moment: a $490 comprehensive audit of a brief or filing, checking every citation for existence, accuracy, and continued validity, with a report suitable for the matter file. It is not a per-citation tool and it is not a subscription — it is the full-brief check a partner runs before the brief goes out.

It does not replace KeyCite or Shepard's for ongoing research. It complements them: citators tell you the history of the cases you found; FirmCited verifies the citations that actually made it into the filing — including the ones that came out of an AI drafting tool and were never in your research workflow at all.

Order a FirmCited audit →

FAQ

What is the difference between a citator and an AI citation checker?

A citator (KeyCite, Shepard's, BCite) tracks the subsequent history of real cases — whether a case was affirmed, reversed, overruled, or limited. An AI citation checker verifies that a citation exists and supports the proposition it is cited for. The two catch different errors. A fabricated case has no history, so a citator cannot flag it; that is the gap the AI tools fill.

How much does citation checking cost?

From $10 per batch to $490 per full-brief audit. Per-citation tools run roughly $10-$30 per batch. Subscription verifiers run about $79/month or $29/document. Citators are included in Westlaw/Lexis/Bloomberg subscriptions. Full-brief audits run a few hundred dollars.

Can a citation checker guarantee my brief has no bad citations?

No tool can guarantee that. Citation checkers reduce the risk substantially, but verification depends on the underlying databases, and the law changes. The professional standard remains: the attorney signing the filing is responsible for its accuracy. A citation audit is evidence of care, not a substitute for it.

Do I still need KeyCite or Shepard's if I use an AI citation checker?

Yes. The AI tools verify existence and support; the citators verify continued validity. A real case that was overruled last month is a citation problem that only the citator will catch. The strongest workflow uses both.

What is the Mata v. Avianca case?

In 2023, a federal court sanctioned two lawyers and their firm for submitting a brief containing six fabricated judicial opinions and citations generated by ChatGPT. The case became the standard cautionary tale for AI-assisted legal writing and is widely cited in ethics opinions on AI use in litigation.

Sources & Citations

• Churci and Ascero AI pricing per their public product pages (2026).
• KeyCite, Shepard's, and BCite are the standard citator services within Westlaw, Lexis, and Bloomberg Law respectively.
• Mata v. Avianca, Inc., 678 F. Supp. 3d 443 (S.D.N.Y. 2023) — sanctions for AI-fabricated citations.

About BizLegal AI: Practitioner-reviewed compliance and legal intelligence. FirmCited is an AI citation audit for law firms; the full product suite is at bizlegal-ai.com.

This article is for informational purposes only and does not constitute legal advice. Consult a qualified professional for your specific matter.