CourtListener API

Free REST API providing access to millions of US federal and state court opinions, oral arguments, dockets, judge data, and legal citations maintained by the nonprofit Free Law Project.

Evaluated Mar 06, 2026 (0d ago) vcurrent
Homepage ↗ Repo ↗ Other legal court-opinions case-law open-source rest-api federal-courts legal-research
⚙ Agent Friendliness
63
/ 100
Can an agent use this?
🔒 Security
77
/ 100
Is it safe for agents?
⚡ Reliability
78
/ 100
Does it work consistently?

Score Breakdown

⚙ Agent Friendliness

MCP Quality
0
Documentation
85
Error Messages
78
Auth Simplicity
90
Rate Limits
82

🔒 Security

TLS Enforcement
100
Auth Strength
72
Scope Granularity
50
Dep. Hygiene
80
Secret Handling
85

Open public data so security model is appropriately lightweight; token auth is sufficient for the use case; no sensitive PII in responses

⚡ Reliability

Uptime/SLA
70
Version Stability
82
Breaking Changes
80
Error Recovery
78
AF Security Reliability

Best When

Building legal research tools, academic projects, journalism, or public-interest applications that need broad access to US case law without enterprise cost barriers.

Avoid When

You need comprehensive coverage of unpublished opinions, real-time PACER document downloads, or SLA-backed uptime guarantees for mission-critical production services.

Use Cases

  • • Searching and retrieving US court opinions by citation, judge, court, or keyword
  • • Building legal research tools that surface case law without enterprise subscription costs
  • • Tracking docket activity and case developments across federal and state courts
  • • Analyzing citation networks and judicial precedent patterns
  • • Powering legal aid platforms and public-interest legal tech applications

Not For

  • • Real-time transactional legal filings (use PACER for federal documents)
  • • International case law outside the US
  • • Proprietary legal analytics requiring Westlaw/LexisNexis depth
  • • High-volume production workloads exceeding free tier limits without arrangement

Interface

REST API
Yes
GraphQL
No
gRPC
No
MCP Server
No
SDK
No
Webhooks
No
OpenAPI Spec ↗

Authentication

Methods: api_key
OAuth: No Scopes: No

Token-based authentication via HTTP Authorization header. Free registration at courtlistener.com. Anonymous access allowed at lower rate limits.

Pricing

Model: free
Free tier: Yes
Requires CC: No

Fully free, nonprofit-operated. Bulk data dumps available for download. Donations welcomed to support operations.

Agent Metadata

Pagination
cursor
Idempotent
Full
Retry Guidance
Documented

Known Gotchas

  • ⚠ Rate limit of 5000/day can be exhausted quickly during bulk citation lookups
  • ⚠ Full-text search relevance scoring is not always predictable for legal query patterns
  • ⚠ Some older opinions have OCR artifacts that affect text quality
  • ⚠ Docket data completeness varies by court and era
  • ⚠ No webhooks means agents must poll for case updates

Alternatives

westlaw-edge-api lexisnexis-api uscourts-pacer-api

Full Evaluation Report

Detailed scoring breakdown, competitive positioning, security analysis, and improvement recommendations for CourtListener API.

$99
API endpoint ↗ Agent guide ↗ Report inaccuracy

Scores are editorial opinions as of 2026-03-06.

5178
Packages Evaluated
26151
Need Evaluation
173
Need Re-evaluation
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