Does this tool catch AI-hallucinated citations?

Yes. Every citation you paste is matched against our database of 9.5 million real court opinions. If a citation does not exist — or if the case name you gave does not match the real case at that citation — we flag it.

What reporters does it cover?

U.S., S.Ct., L.Ed., L.Ed.2d, F., F.2d, F.3d, F.4th, F.Supp., F.Supp.2d, F.Supp.3d, F.App'x, and major state reporters including So.2d/3d, N.E.2d/3d, N.W.2d/3d, P.2d/3d, S.E.2d/3d, S.W.2d/3d, A.2d/3d, Cal./Cal.Rptr., N.Y.S.2d, Ill.App., and more.

Is this tool really free?

The first 3 checks per day are free with no signup. After that, a free Ark Legal AI account unlocks unlimited checks.

Free Citation Checker

Paste any brief, memo, or motion. We verify every case citation against 9.5 million U.S. court opinions and flag hallucinated cases, wrong reporters, and name mismatches — in seconds.

9.5M+Opinions indexed

50States + federal

FreeNo signup for 1st use

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How it works

Paste your brief

Any legal document with citations — motions, memos, appellate briefs, scholarly articles.

We extract every citation

Federal and state reporters — U.S., F.3d, F.Supp.3d, So.3d, N.E.2d, P.3d, and dozens more.

Real-case verification

Every citation is matched against 9.5M real opinions. Hallucinations, wrong reporters, and bad case names are flagged.

Catches AI hallucinations

ChatGPT and Claude confabulate fake citations. We catch them by checking every reference against real court records.

Detects name mismatches

When the case you cited doesn't match the real case at that citation, we flag it — the #1 symptom of AI hallucination.

All 50 states + federal

From U.S. Supreme Court to state supreme courts to federal district and appellate courts.

No signup for your first 3 checks

Try it on your current brief. Create a free account for unlimited checks.