Case Law Research

Search millions of US court cases with Boolean operators and filters

Search millions of cases across US federal and state courts using natural language, Boolean operators, or citation strings.

Search Methods

Natural Language

Describe what you’re looking for:

“Cases where the court discussed qualified immunity in excessive force claims”

Boolean Operators

Operator	Example	Effect
AND	murder AND conviction	Both terms must appear
OR	negligence OR malpractice	Either term can appear
NOT	appeal NOT dismissed	Excludes the term
"..."	"beyond reasonable doubt"	Exact phrase
( )	(murder OR homicide) AND conviction	Grouped conditions

Citation Lookup

Search by citation string directly:

“410 U.S. 113”

Citation strings are resolved in Bluebook and standard US reporter formats.

Filters

Jurisdiction

US federal and state courts

Court

Specific courts or tribunals (e.g. SCOTUS, 9th Circuit, state supreme courts)

Year / Date range

Cases from a particular period

Judge

Cases authored or joined by a specific judge

Result Fields

Every search result returns:

• Case title and citation - all known citation strings
• Court and date
• Judges - bench composition
• Relevance score - 0 to 1, calibrated per query
• Snippet - matching passage from the judgment with the query terms highlighted

Filter by Court first to cut noise. A query for “qualified immunity” against all US courts returns thousands of opinions; the same query scoped to 9th Circuit, 2020-present is immediately practitioner-ready.

API

The case law search API lets you embed legal research directly into your product. Common use cases:

• Contract drafting platforms that surface relevant precedents during drafting
• Practice management tools with built-in case law lookup
• Compliance systems that cross-reference regulations against case law
• Internal legal portals for enterprise legal teams

Search Endpoint

curl -X POST https://api.vaquill.ai/api/v1/research/search \
  -H "Authorization: Bearer vq_key_..." \
  -H "Content-Type: application/json" \
  -d '{
    "query": "qualified immunity excessive force",
    "court": "supreme_court",
    "year_from": 2015,
    "year_to": 2024,
    "limit": 10
  }'

Each search call costs 1 credit (1-20 results) and scales up to 3 credits for 51-100 results. See Credits for the full pricing schedule and the API Reference for parameters.

Ready-to-run prompt

Doctrine survey - find the leading cases on a doctrine, group by circuit, flag splits.

CopiedCopy prompt

Related

Citations

Resolve, search, and traverse the citation network.

Citation Graph

Walk the forward and backward citation graph from any case.

Deep Research

Multi-hop reasoning when the answer needs more than one search.

Agent Mode

Autonomous research across cases, statutes, and the web.