The match score explained - what a 78% match means in AI case search
By LegiMatch Research Team · Published October 14, 2026 · Updated October 21, 2026 · 3 min read
Short answer: the match score is a weighted combination of five factors - facts (40%), legal issues (30%), statutes (15%), jurisdiction (10%) and recency (5%) - each shown separately. It tells you which decisions to read first. It is not a probability of winning and not a measure of whether a case is good law.
The five factors
| Factor | Weight | A high score means |
|---|---|---|
| Facts | 40% | The decision's facts are close in meaning to your fact summary |
| Legal issues | 30% | The decision addresses the same legal questions you listed |
| Statutes | 15% | It applies the same statute sections (or the same chapter) |
| Jurisdiction | 10% | It's from your state, and from a court whose decisions bind yours |
| Recency | 5% | It's more recent |
When a factor can't be measured - for example your matter cites no statute - its weight is shared proportionally among the others, so missing information never drags a score down.
In an AI search, the AI also reads each top candidate next to your matter; its 0-100 similarity rating counts for half the score, and the five factors above make up the other half. A decision later overruled stays listed with a red warning, its score lowered by a fifth.
Why good matches score 70-90%, not 100%
A 100% score would mean an identical case: same facts, same issues, same statutes, same court, decided this year. Real precedent almost never lines up that way. In practice:
- 85% and above - very close on facts and issues; read these first
- 70-85% - strong candidates; usually share the key facts or the same legal question
- 55-70% - related; often useful for a specific point (one issue, one statute)
- below 55% - loosely related; check only if the closer results are thin
The breakdown is more useful than the total. A case with a 95% facts score but a low issues score may be the perfect factual analogy decided on a different ground - worth knowing either way.
What the score is not
- Not a prediction. It says nothing about how your matter will be decided.
- Not a good-law check. A decision can match closely and still have been reversed. LegiMatch shows good-law flags separately, and you should always verify treatment yourself.
- Not a ranking of legal merit. A short memorandum opinion can match your facts better than a landmark decision.
Reading the score in practice
- Sort by match, read the top five decisions' facts sections.
- Use the factor breakdown to spot why each ranked: facts, issues or jurisdiction.
- Switch the sort to outcome or date when you need favorable or recent authority.
- Re-weight the factors if your priority differs - for example raise jurisdiction when you need binding authority only. Re-ranking doesn't use AI credits.
Frequently asked questions
Why is my best case only 76%?
Usually because it differs on one factor - another state, an older decision, or a different statute. Check the breakdown: if facts and issues are high, it's likely a strong analogy.
Can I change the weights?
Yes. You can re-weight facts, issues, statutes, jurisdiction and recency for a research result without spending AI credits.
Does a higher score mean the case is more likely to help me?
Not necessarily. The score measures similarity, not whether the outcome favors your client. Read the outcome and the reasoning of every case before relying on it.
Is the match score the same as a citator flag?
No. Good-law flags come from how later decisions treated a case. The match score only measures similarity to your matter.
This article is general information about legal research, not legal advice. Verify every authority before relying on it.
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