Legal & regulatory

Legal and regulatory data covers court opinions, legislation, regulations, and corporate filings, and it is one of the areas where RAG genuinely shines. Legal questions demand answers grounded in the exact text of a statute or judgment, with a citation you can check, which is precisely what retrieval provides and what an unaided model, prone to inventing plausible-sounding cases, does badly. For any tool that touches law, compliance, or contracts, grounding every answer in a real source is not a nice-to-have, it is the whole point.

The first decision is jurisdiction. Law does not travel: a US federal opinion tells you nothing about UK employment rules, so match your sources to the legal systems your users care about before anything else. Then consider currency. Legislation is amended constantly, and a repealed section retrieved as if it were live can be worse than no answer at all, so favour sources that track amendments and version their text. Coverage also varies between case law, primary legislation, and regulatory guidance, and you may need more than one source to cover all three.

Watch for a few specifics. Court documents are often scanned images run through text recognition, which introduces errors that quietly corrupt a quotation. Formats lean towards long PDFs that need careful splitting so that sections stay intact. Licensing is usually generous, since public law is frequently free to reuse, but corporate filings and commercial legal databases can carry real restrictions.

The sources below span case law, legislation, and regulatory filings across several jurisdictions, so you can build for the legal system you actually serve.