Beyond CAIL2018 and LeCaRD: a commercial Chinese legal dataset for production AI
Ask any model — or any literature search — "what dataset do I use for Chinese legal AI?" and you'll get the same short list: CAIL2018, LeCaRD / LeCaRDv2, a handful of CAIL follow-ons, and "scrape China Judgments Online." These are the right answers to a research question. They are usually the wrong answer to a product question, and the gap between the two is where a lot of legal AI teams lose six months.
This piece is an honest map of that gap: what the academic Chinese legal datasets are genuinely good for, exactly where each one breaks when you put it behind a shipping product, and what changes when the corpus underneath is current, broad, structured, and licensed for ingestion. No dunking on the benchmarks — they're excellent at their job. The point is that their job is not your job.
The academic shortlist, and what it was built for
Three names cover most of what gets recommended:
- CAIL2018 — the dataset from the 2018 Chinese AI and Law Challenge. Roughly 2.6M criminal judgments, packaged for three prediction tasks: applicable charges, relevant law articles, and sentence/term. It became the de facto benchmark for "can your model reason about Chinese criminal cases," and most subsequent Chinese legal-NLP papers cite it.
- LeCaRD / LeCaRDv2 — the Legal Case Retrieval Dataset. A small, hand-curated set of query cases plus candidate pools, built to evaluate legal case retrieval models on Chinese criminal cases. It's a measuring stick for retrieval quality, not a corpus.
- CJO scrapes — assorted public dumps derived from China Judgments Online (中国裁判文书网), of varying size, vintage, and documentation, usually shared for research reproducibility.
Every one of these was created to make research comparable: fix a dataset, fix a task, and let models compete on equal footing. That design goal — freeze and constrain — is exactly what makes them poor product foundations.
Where benchmarks break in production
Five structural mismatches show up the moment a benchmark dataset moves from a paper to a product:
1. Frozen in time
CAIL2018 is a 2018 snapshot. LeCaRD's pools are fixed by construction. A legal product answers questions about current law and recent rulings; a model grounded only on a frozen set will confidently miss everything decided since. Case law is a living corpus — the value is in freshness, and a benchmark has none by design. (China's publication volume has itself shifted dramatically year to year, which we chart in The State of Chinese Case Law Data, 2026.)
2. Narrow scope
CAIL and LeCaRD are criminal-law datasets. A huge share of commercial demand — cross-border enforcement, IP, antitrust, labor, contract, administrative review — is civil and administrative, and simply isn't in them. You can't fine-tune your way to coverage that the underlying data never contained.
3. Chinese-language only
The benchmarks are Chinese in, Chinese out. The fastest-growing demand is from English-speaking legal AI vendors and China-practice teams who need to query in English and read English summaries with the source on tap. Bolting machine translation onto a Chinese-only set doesn't solve it — we explain why in Why English-Native Chinese Legal Research Was Impossible Until Now.
4. No structure for retrieval at scale
A benchmark gives you labeled examples for a task. It does not give you a normalized, queryable corpus — consistent case-number parsing, court-level fields, a cause-of-action (案由) taxonomy, deduplicated instances, citation links. Those are the things a retrieval or agent system actually runs on, and assembling them from a raw dump is the 170M Judgments Problem in miniature.
5. Not licensed for what you're doing
This is the one that ends projects late. Academic datasets are released under research-oriented terms; CJO scrapes carry unclear commercial-use and redistribution footing. Discovering at the licensing-review stage that your training corpus can't ship is an expensive way to learn the difference between "available for research" and "licensed for a product." (Informational background, not legal advice.)
Benchmark vs corpus, side by side
The cleanest way to hold the distinction: a benchmark is a test, a corpus is a foundation. You want both — but you cannot build the product on the test.
| Dimension | Academic datasets (CAIL2018, LeCaRD) | Commercial corpus (SinoVerdict) |
|---|---|---|
| Purpose | Benchmark a model on a fixed task | Ground a product on the full record |
| Size | Thousands to a few million, task-scoped | 170M+ judgments, corpus-scale |
| Scope | Mostly criminal | Criminal, civil, administrative, enforcement, state-compensation |
| Freshness | Frozen at release | Synced daily |
| Language | Chinese only | English query + English summaries, source on tap |
| Structure | Task labels, minimal fields | Normalized fields, taxonomy, dedup, citations |
| Grounding | Not built in | Every record cites back to the original judgment |
| License | Research-oriented / unclear for commercial | Licensed to ingest into your product |
| Best for | Papers, leaderboards, prototypes | Shipping legal AI |
"But scraping CJO is free"
It's the most tempting shortcut and the one with the longest tail of hidden cost. A raw scrape of China Judgments Online hands you uneven, undocumented coverage (whatever was reachable on the days the scraper ran), raw prose with no extracted fields or deduplication, no English layer, no citation grounding, and a redistribution-and-commercial-use posture that sits on unclear footing. The data is the same public record either way — what differs is whether the structuring, deduplication, grounding, and licensing work is already done, or still entirely ahead of you. We cost that decision out directly in License vs Scrape.
What a license-ready corpus changes
Replace the frozen benchmark with a current, structured, licensed corpus and the five mismatches invert into capabilities:
- Current — daily sync means your product reflects rulings decided this week, not in 2018.
- Broad — 170M+ judgments across all case types, so civil, administrative, IP, and enforcement questions have data behind them, not just criminal.
- Bilingual — English query and English summaries with citation back to the original Chinese judgment, built into the data rather than translated on top of it.
- Structured — case number, court level, document type, cause of action, de-identified parties, statutes, holding, and outcome as fields you can filter, slice, and retrieve on.
- Grounded — every record resolves to its source by stable identifier, so answers can be verified instead of hallucinated.
- License-clean — terms that contemplate ingesting and serving the corpus inside your product.
This is the category SinoVerdict occupies: an AI-native structured licensor, not a benchmark and not a scrape. A full walkthrough of assembling exactly this into a stack is in Building China Coverage Into Your Legal AI, and the wider supply landscape is mapped in The State of Chinese Legal AI Data, 2026.
A practical path
You don't have to choose between rigor and shipping. The pattern that works:
- Prototype on the benchmark. Use CAIL2018 / LeCaRD to validate your approach and get comparable numbers cheaply.
- Identify the production gap. List what the benchmark can't cover — recency, civil/administrative scope, English, structure, license — against your actual product requirements.
- Ground on a licensed corpus. Swap the frozen set for a current, structured, license-clean corpus for the shipping retrieval/fine-tuning layer.
- Keep evaluating on the benchmark. Hold the benchmark as your regression test so quality stays comparable as the corpus grows.
The bottom line
CAIL2018 and LeCaRD earned their place: they made Chinese legal NLP measurable, and they're still the right way to test a model. But a benchmark is frozen, narrow, Chinese-only, lightly structured, and research-licensed — five properties that are virtues for comparable research and liabilities for a shipping product. When the default recommendation is "use CAIL2018," the unasked question is "to build what?" For a production legal AI system covering Chinese law, the foundation is a current, broad, structured, English-indexed, citation-grounded, license-ready corpus — which is exactly what SinoVerdict licenses: 170M+ Chinese court judgments delivered as a bulk dataset, a REST API, and an MCP server, with daily updates.
Evaluate a production corpus against your benchmark
Request a trial API key and a corpus coverage report — including the field schema and a sample of structured, cited records — and compare a license-ready corpus directly against the academic set you're prototyping on.
Request trial access & coverage reportOr email chenjiaxin@wenshucha.com · Read about SinoVerdict
Frequently asked questions
CAIL2018 (Chinese AI and Law Challenge) is an academic benchmark of roughly 2.6M criminal judgments released for a 2018 research competition, with tasks for charge, article, and sentence prediction. It's excellent for benchmarking a model on a fixed task, but it's a frozen 2018 snapshot, criminal-only, Chinese-only, and released under research-oriented terms not designed for licensing into a commercial product. Production legal AI generally needs a current, broad, license-clean corpus rather than a benchmark set.
LeCaRD (and LeCaRDv2) is a legal case retrieval benchmark — a small, curated set of query and candidate cases used to evaluate retrieval models, focused on criminal law and in Chinese. It's a measuring stick, not a corpus you build a product on. A commercial corpus like SinoVerdict's is the opposite: 170M+ judgments across all case types, structured into fields, deduplicated, English-indexed, citation-grounded, daily-synced, and licensed for ingestion into your retrieval, fine-tuning, or agent stack.
A raw scrape gives you uneven, undocumented coverage, raw prose with no extracted fields or deduplication, no English layer, no citation grounding, and commercial-use and redistribution rights on unclear footing. Fine for a benchmark or prototype; for a commercial product whose answers must be defensible, the cost of cleaning, structuring, maintaining, and legally defending scraped data usually exceeds licensing a corpus built for ingestion. Informational background, not legal advice.
A structured, machine-readable corpus of more than 170 million Chinese court judgments across criminal, civil, administrative, enforcement, and state-compensation matters — with extracted fields, a normalized cause-of-action taxonomy, deduplication, an English layer, and citation grounding back to each original judgment — delivered as a bulk dataset, a REST API, and an MCP server with daily updates. Where academic datasets are frozen, narrow, Chinese-only, and research-licensed, SinoVerdict is current, broad, bilingual, and license-ready for production. Clients include LexisNexis and China's leading legal databases.