How LegiMatch search works - from your facts to real, linked court decisions
By LegiMatch Research Team · Published October 14, 2026 · Updated October 21, 2026 · 3 min read
Short answer: you describe your matter in plain English or upload a complaint, brief or memo. LegiMatch identifies the facts, legal issues, statutes and jurisdiction, lets you correct them, and returns real US court decisions ranked by how closely they match - each with a visible match score and a link to the court's own text. It only ever returns decisions that exist in its library of published opinions.
The library
LegiMatch searches public-domain US court opinions - the courts' own text, with parties, judges, dates, citations and original page numbers for pinpoint cites. It contains no publisher headnotes or editorial summaries. Coverage includes state supreme and intermediate appellate courts, the federal courts of appeals and the US Supreme Court, and new decisions are added every day.
Step 1: tell LegiMatch about your matter
Paste a few paragraphs of facts, or upload a PDF or Word document. LegiMatch identifies:
- a neutral fact summary
- the legal issues involved
- any statutes you cite
- the jurisdiction
You can review and edit all of it before searching. Personal identifiers such as emails, phone numbers and Social Security numbers are redacted automatically.
Step 2: results ranked by how well they match
LegiMatch looks for decisions whose facts are like yours even when the wording is completely different - "slipped on water in the produce aisle" finds "fell on a liquid near the store entrance". It also follows the precedent courts themselves relied on, the way an experienced researcher would.
Step 3: a match score you can see inside
Every result gets a match score from five factors, each shown separately:
| Factor | Weight | What it measures |
|---|---|---|
| Facts | 40% | How close the decision's facts are to yours |
| Legal issues | 30% | Overlap between your issues and the decision's |
| Statutes | 15% | Same sections, or the same chapter |
| Jurisdiction | 10% | Same state, and whether the court can bind yours |
| Recency | 5% | Newer decisions score a little higher |
If a factor can't be measured - for example your matter cites no statute - its weight is shared among the others, so the score isn't dragged down by missing input. In an AI search, the AI also reads each top candidate next to your matter, and its 0-100 similarity rating counts for half the match score, with the five factors as the other half. A decision that was later overruled stays in the list with a red warning, its score lowered by a fifth. You can re-weight the factors for any result without spending AI credits.
Step 4: read, verify, save
Each result shows the outcome, a short "why it matches" and "key difference" note (clearly labeled as AI-written), whether the decision is still good law, and a one-click link to the full opinion with pinpoint pages. Save results to a matter, export a report to PDF or Word, or send it to Clio.
What LegiMatch never does
- It never invents a citation. Every result is a real decision from the library, linked to the court's text.
- It doesn't give legal advice or predict how your matter will be decided.
- It doesn't train AI models on your documents.
Frequently asked questions
Does LegiMatch use ChatGPT to search?
No. LegiMatch searches its own library of real court decisions. AI helps describe why a result matches, but it never decides which cases exist - every result is a stored decision with a link to the court's text.
Why do two searches with similar facts give different results?
Small changes in the issues or statutes you list change the ranking, because issues carry 30% of the score and statutes 15%. Review the extracted issues before searching.
Which courts are included?
State supreme and intermediate appellate courts, the federal courts of appeals and the US Supreme Court. Coverage grows daily as new decisions are published.
Can I see why a case ranked where it did?
Yes. Each result shows its five factor scores, so you can see whether it ranked on facts, issues, statutes, jurisdiction or recency.
This article is general information about legal research, not legal advice. Verify every authority before relying on it.
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