Case Law Search
AI Case Law Search:
Find Controlling Authority
in Minutes, Not Hours
The Law Lion's case law search tool finds relevant US federal and state case law by legal issue, jurisdiction, and court level — in natural language. No Boolean operators. Returns case summaries, holdings, and Bluebook-formatted citations ready to insert into your draft.
How Case Law Search Works
3 inputs. Relevant results in under 2 minutes.
Legal Issue or Question
State the issue in plain English: 'Does the economic loss rule bar negligence claims in product liability cases under Texas law?' The Law Lion identifies the relevant doctrine.
Jurisdiction
Select the applicable federal circuit or state. Results are filtered to controlling authority first, followed by persuasive authority from other circuits.
Court Level (Optional)
Filter by Supreme Court, circuit court, district court, or state court hierarchy. Useful for procedural issues or constitutional questions.
Search Coverage: Federal and State Courts
Comprehensive coverage across the entire US court system.
| Court System | Coverage |
|---|---|
| US Supreme Court | All decisions since 1791 |
| US Courts of Appeals | All 13 circuits — published and unpublished |
| US District Courts | All 94 districts — published and select unpublished |
| State Supreme Courts | All 50 states + D.C. — full coverage |
| State Appellate Courts | All 50 states — published; select unpublished |
| State Trial Courts | Select decisions in CA, NY, TX, FL, IL, and other high-volume states |
Citator Signals: Is the Case Still Good Law?
The most dangerous citation error is citing a case that has been overruled without knowing it. Every case result includes a citator signal.
Positive
The case has been followed or cited favorably. No negative treatment identified.
Caution
The case has been distinguished, questioned, or limited. Review subsequent history before citing.
Negative
The case has been overruled, reversed, or vacated. Do not cite as authority without understanding the current posture.
Neutral
The case has been cited but without positive or negative treatment. Typically safe to cite with verification.
Circuit Splits: Researching Unsettled Law
When the circuits disagree, the research problem is harder. The Law Lion identifies circuit splits on contested legal issues.
Majority Position
Circuits that have adopted the majority position with lead cases identified.
Minority Position
Circuits that have adopted the minority position with lead cases identified.
Open Circuits
Circuits where the issue remains open, noting district court decisions that have addressed it.
Supreme Court Status
Whether the Court has taken up the issue or denied cert on related cases.
Time Savings: AI vs. Traditional Research
Time estimates reflect experienced attorney research time. Results vary by issue complexity.
| Research Task | Traditional Platforms | The Law Lion | Saved |
|---|---|---|---|
| Find controlling standard for motion type | 45-90 min | 3-8 min | ~90% |
| Locate circuit split on contested issue | 2-3 hours | 10-20 min | ~85% |
| Find 5 supporting cases on a legal element | 30-60 min | 5-10 min | ~85% |
| Verify a single citation is good law | 5-10 min | < 1 min | ~90% |
| Research 3-issue brief | 4-6 hours | 30-50 min | ~87% |
Frequently Asked Questions
Yes. The Law Lion covers all 13 US Courts of Appeals, all 94 US District Courts, and the US Supreme Court — published and unpublished opinions. State court coverage extends to all 50 states and D.C.
Yes. Enter a case name, citation, or docket number to retrieve the full case summary, holding, and citator signal for a specific decision.
Results are ranked by relevance to the legal issue queried, with controlling authority for the selected jurisdiction ranked first. More recent decisions are weighted higher than older ones.
Yes. Unpublished opinions are included and clearly flagged. Under FRAP 32.1, unpublished federal opinions issued after January 1, 2007 may be cited in federal court.
No. The citator signals provide a current-status check that surfaces obvious bad law. For final verification before filing, attorneys should Shepardize or KeyCite to confirm the full citation history.