Case Search

Find cases by topic and discover related authorities

Search for legal sources by topic, find similar cases, and conduct deep research with multiple query variations.

Find cases

Search for legal sources including cases, statutes, and regulations from authoritative databases.

Endpoint

POST /legal/v1/find

cURL

curl -X POST https://api.case.dev/legal/v1/find \
  -H "Authorization: Bearer $CASEDEV_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "query": "qualified immunity excessive force police",
    "jurisdiction": "us-federal",
    "numResults": 10
  }'

Parameters

Parameter	Type	Description
query	string	Search query (3-1,000 characters)
jurisdiction	string	Optional jurisdiction ID (e.g., us-federal, california)
numResults	number	Results to return (1-25, default 10)

Response

{
  "query": "qualified immunity excessive force police",
  "jurisdiction": "us-federal",
  "found": 10,
  "candidates": [
    {
      "url": "https://www.courtlistener.com/opinion/...",
      "title": "Harlow v. Fitzgerald, 457 U.S. 800 (1982)",
      "snippet": "Government officials performing discretionary functions are shielded from liability...",
      "source": "courtlistener.com",
      "publishedDate": "1982-06-24"
    }
  ],
  "hint": "IMPORTANT: Use legal.verify() on each candidate before citing."
}

Always verify before citing. Search results are candidates, not verified sources. Use legal.verify() to confirm each citation exists in the database before your user cites it.

---

Find similar cases

Given a legal document URL, find semantically similar sources. Useful for expanding research or finding citing cases.

Endpoint

POST /legal/v1/similar

cURL

curl -X POST https://api.case.dev/legal/v1/similar \
  -H "Authorization: Bearer $CASEDEV_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "url": "https://www.courtlistener.com/opinion/118365/bush-v-gore/",
    "numResults": 10
  }'

Parameters

Parameter	Type	Description
url	string	URL of the source document
jurisdiction	string	Optional jurisdiction filter
numResults	number	Results to return (1-25, default 10)
startPublishedDate	string	Only include sources after this date (ISO format)

Response

{
  "sourceUrl": "https://www.courtlistener.com/opinion/118365/bush-v-gore/",
  "jurisdiction": "all",
  "found": 10,
  "similarSources": [
    {
      "url": "https://www.courtlistener.com/opinion/...",
      "title": "Reynolds v. Sims, 377 U.S. 533 (1964)",
      "snippet": "The Equal Protection Clause requires substantially equal legislative representation...",
      "source": "courtlistener.com",
      "publishedDate": "1964-06-15"
    }
  ]
}

---

Deep research

Conduct comprehensive research with multiple query variations. Uses advanced search to find sources across different phrasings of the legal issue.

Endpoint

POST /legal/v1/research

cURL

curl -X POST https://api.case.dev/legal/v1/research \
  -H "Authorization: Bearer $CASEDEV_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "query": "employment discrimination disparate impact",
    "additionalQueries": [
      "Title VII disparate impact theory",
      "Griggs v Duke Power significance"
    ],
    "numResults": 15
  }'

Parameters

Parameter	Type	Description
query	string	Primary search query
additionalQueries	string[]	Up to 5 alternative phrasings
jurisdiction	string	Optional jurisdiction filter
numResults	number	Results to return (1-25, default 10)

Response

{
  "query": "employment discrimination disparate impact",
  "additionalQueries": ["Title VII disparate impact theory", "..."],
  "jurisdiction": "us-federal",
  "searchType": "deep",
  "found": 15,
  "candidates": [
    {
      "url": "https://www.courtlistener.com/opinion/...",
      "title": "Griggs v. Duke Power Co., 401 U.S. 424 (1971)",
      "snippet": "The Act proscribes not only overt discrimination but also practices...",
      "highlights": [
        "Congress directed the thrust of the Act to the consequences of employment practices",
        "The touchstone is business necessity"
      ],
      "source": "courtlistener.com",
      "publishedDate": "1971-03-08"
    }
  ]
}

When to use deep research

Scenario	Use
Quick case lookup	legal.find()
Thorough brief research	legal.research() with query variations
Finding all related cases	legal.similar() from a key case

---

Common patterns

Research workflow

cURL

# 1. Deep search with variations
curl -X POST https://api.case.dev/legal/v1/research \
  -H "Authorization: Bearer $CASEDEV_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "query": "topic",
    "additionalQueries": ["variation 1", "variation 2"],
    "jurisdiction": "us-federal",
    "numResults": 20
  }'

# 2. Verify top candidates
curl -X POST https://api.case.dev/legal/v1/verify \
  -H "Authorization: Bearer $CASEDEV_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "text": "Candidate Title, 457 U.S. 800"
  }'

# 3. Find similar cases to the best result
curl -X POST https://api.case.dev/legal/v1/similar \
  -H "Authorization: Bearer $CASEDEV_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "url": "https://www.courtlistener.com/opinion/...",
    "numResults": 5
  }'

Build a case timeline

cURL

# Find the seed case
curl -X POST https://api.case.dev/legal/v1/find \
  -H "Authorization: Bearer $CASEDEV_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "query": "seed case topic",
    "numResults": 1
  }'

# Find similar cases across time
curl -X POST https://api.case.dev/legal/v1/similar \
  -H "Authorization: Bearer $CASEDEV_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "url": "https://www.courtlistener.com/opinion/...",
    "numResults": 25
  }'

Jurisdiction-specific research

cURL

curl -X POST https://api.case.dev/legal/v1/find \
  -H "Authorization: Bearer $CASEDEV_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "query": "your query",
    "jurisdiction": "us-federal",
    "numResults": 5
  }'

Supported sources

Search covers authoritative legal databases:

Source	Content
CourtListener	~10M court opinions
Cornell Law	Statutes, regulations, legal encyclopedias
Supreme Court	All SCOTUS opinions
govinfo.gov	Federal Register, CFR, USC
State courts	Via regional reporters