OpenCaseLaw

Open Swiss case law and legislation for legal research and AI.

1M+ decisions · all 26 cantons · 1875–today · citation graph · MCP + REST + CLI + Parquet · CC0 data · MIT code

Try the search · Chat with your AI · Automate research · Download the dataset · API documentation

What you can do

• Find Swiss decisions across federal and cantonal courts, in German, French and Italian.
• Trace citations between cases and identify the leading decisions on a question.
• Query case law and legislation from Claude, ChatGPT-compatible clients, or any MCP client.
• Save repeatable research scripts, inspect citation resolution, and preserve selected evidence with the research CLI.
• Download the corpus for legal NLP, retrieval and graph research.

Connect in 30 seconds

{
  "mcpServers": {
    "opencaselaw": {
      "url": "https://mcp.opencaselaw.ch/mcp"
    }
  }
}

No sign-up, no API key, read-only. 42 tools; setup guides for individual clients are at opencaselaw.ch/mcp.

Using Anthropic's Claude for Legal plugin? A Swiss playbook that makes its contract-review and NDA-triage skills work under Swiss law, every article verified against the statute mirror, is at opencaselaw.ch/claude/legal.local.md; see the setup guide.

Automate research

ocl is a small command-line client over the public research API, made for two jobs a chat window does badly: checking the citations in a draft, and keeping the evidence behind a memo in a folder you can share. It is on PyPI as opencaselaw-cli:

pipx install opencaselaw-cli        # or: uv tool install opencaselaw-cli
ocl citations resolve 'BGE 136 III 513' '4A_747/2012' 'BGE 999 III 1'
ocl bundle create 'Rachekündigung Art. 336 OR' --max-results 10 --passage 2 --law OR:336 --out evidence

The first prints, per reference, whether the decision exists, which one it is, and whether a requested Erwägung exists. The second saves the selected decisions, passages and statute articles into a folder with a plain-language INDEX.md and a hashed manifest.json. Everything comes back from the service unchanged: citation strings, passage text, source links. Search is bounded, and a citation check establishes existence, not that an authority supports a proposition. See the CLI guide.

Use MCP for conversations, the CLI or REST API for automation, and Parquet for corpus-scale analysis.

A real result

Question. When is a dismissal in retaliation for an employee asserting a claim abusive under Swiss law?

One call — search_decisions("missbräuchliche Kündigung Rachekündigung") returns 129 decisions, the leading one first:

BGE 136 III 513 (7 October 2010)

Art. 336 OR; missbräuchliche Kündigung. Der Arbeitnehmer ist vor einer Rachekündigung nur geschützt (Art. 336 Abs. 1 lit. d OR), sofern er nach Treu und Glauben annehmen kann, dass die von ihm geltend gemachten Ansprüche berechtigt sind. Es ist nicht erforderlich, dass sie tatsächlich begründet sind.

The Regeste is returned verbatim from the stored official head-note, and the citation string comes from a stored field — tools never construct citations. That contract is what makes the answer checkable rather than plausible.

Reproduce it:

curl -sG https://mcp.opencaselaw.ch/api/decisions \
  --data-urlencode "q=missbräuchliche Kündigung Rachekündigung" \
  --data-urlencode "limit=3"

Coverage

Counts are generated from one source of truth, docs/canonical_numbers.md, with the verification method recorded alongside each figure.

Limitations, stated plainly. Coverage is not complete where portals restrict access; those sources are documented rather than glossed. The citation graph reports resolution coverage (93.8 %), which is not a precision estimate — a human semantic audit is in preparation. Some cantonal decisions may be published unredacted by the court; we inherit upstream pseudonymisation and do not re-pseudonymise. See governance and removal policy.

Contributing

Data-quality reports are the most valuable contribution — every one so far has been reproduced, fixed and pinned with a regression test. See CONTRIBUTING.md.

The remainder of this page is reference detail.

Why this exists

Swiss legal research today is fragmented across paywalls, inaccessible to language models, and prohibitively expensive for the people who need it most — law students, independent researchers, and anyone outside the major firms. Commercial databases (Weblaw, Swisslex, Legalis) charge hundreds of francs per month and still don't expose a clean API. LLMs hallucinate statute text because they have no authoritative source. Small cantons publish decisions in PDF archives nobody indexes.

OpenCaseLaw fixes this. Every published Swiss court decision, every federal and cantonal law, the resolved citation graph between them, and 44 MCP tools (42 remote in public mode + 2 local-only) that let any modern LLM act as a Swiss legal research assistant — all free, all open, all refreshed automatically.

What you get

Case law — 1,050,000+ decision records (~909,000 unique decisions; cross-identifier duplicates retained and linked, never deleted) from 1875 to today across 118 courts, full text + structured metadata, covering:

• All 7 federal courts (BGer, BVGer, BStGer, BPatGer, BGE, BGE historical, BGE-EGMR)
• Federal military court (Militärkassationsgericht / MKG, 1,244 decisions 1915–2025)
• All 26 cantonal court systems (first, second, and third instance)
• Regulatory decisions (FINMA, ComCo, FDPIC, IndepBC, ElCom, PostCom, ComCom)
• ECHR/EGMR: the Swiss-respondent material (487 BGE-published EGMR translations, 847 HUDOC Switzerland-tagged) plus every ECtHR Chamber and Grand Chamber judgment of importance 1–3 against any of the 46 respondent states — 8,275 judgments, in French where the Court published a French text and English otherwise. Importance 4 (low-importance and repetitive, which is the entire Committee docket) and admissibility decisions are out of scope.
• Three official languages: German 463,012 (46.7%), French 446,869 (45.1%), Italian 81,796 (8.2%); schema reserves rm for Romansh
• Deduplicated via docket normalisation + content-length-aware merge
• Updated daily; BGer decisions available within ~15 minutes of court publication

Legislation — every Swiss law, federal and cantonal, locally mirrored with article-level indexing:

• 5,525 federal laws / ~133,359 articles in each of DE/FR/IT from the Fedlex SPARQL endpoint
• 15,600 cantonal laws / 361,430 articles, direct-scraped from all 26 cantons (LexWork covers 18, SIL covers 2, ZH OpenData covers ZH, TI~RL covers TI); LexFind PDF fallback supplements 4 cantons for laws missing from their primary portals
• Unified SQLite FTS5 search federates both corpora; sub-millisecond article lookup
• Monthly refresh on the 2nd of each month (the day after laws enter into force)
• 12.4 M resolved links from decisions to individual statute articles

Citation graph — the only public large-scale citation graph of the Swiss legal system:

• 9.65 M resolved decision-to-decision citation edges (10 M extracted) with confidence scores
• 12.4 M decision-to-statute links resolved against the current consolidated text
• Bidirectional lookup, appeal-chain resolution (Instanzenzug), leading-case ranking by citation authority
• Powers find_leading_cases, find_citations, find_appeal_chain, analyze_legal_trend (top: BGE 125 V 351 with 85,108 incoming citations)