What it is and who it's for
CoCounsel is a legal AI assistant from Thomson Reuters with authoritative access to Westlaw and Practical Law: research, document analysis, case preparation and verification against vetted legal sources. It's for lawyers and firms where accuracy and grounding in an official legal database matter more than the open internet. What sets it apart is exactly that integration with Thomson Reuters' reference sources.
Key features
- Legal research built on Westlaw (authoritative sources, citations).
- Access to Practical Law (practice guides, templates).
- Document analysis and comparison, fact extraction.
- Case preparation, review of large document sets.
- Source-grounded answers that reduce the risk of hallucinations.
- Enterprise-grade security and integrations.
Get started in 5 minutes
- Access goes through Thomson Reuters — sign up or request it on the CoCounsel page.
- Connect Westlaw/Practical Law under your subscription.
- Hand it research and analysis tasks — you get answers grounded in authoritative sources.
When to use it, and when not to
- ✅ Use it if: you need legal research grounded in Westlaw/Practical Law with maximum reliability.
- ✅ Use it if: you're already inside the Thomson Reuters ecosystem.
- ❌ Skip it → go with "Spellbook" if the job is contract review and drafting right inside Word.
- ❌ Skip it → go with "Harvey" if you need a flexible agent platform for your firm's custom legal workflows.
The honest price
Paid, on a Thomson Reuters subscription (often bundled with Westlaw/Practical Law); pricing is individual/enterprise. Exact figures are with the provider and change over time.
Gotchas
- You get the most value with a Westlaw/Practical Law subscription — that's a separate cost.
- Content is oriented toward specific jurisdictions — check applicability for Russian law.
- AI answers still need a lawyer's review.
- Expensive for small practices.
🤖 Prompt accelerator
"I'm evaluating CoCounsel (Thomson Reuters) for legal research. Help me draft questions for a pilot: coverage of the jurisdictions and practice areas we need, how Westlaw/Practical Law are used in answers, verifiability of citations, data security. Give me criteria for comparing research quality on our typical queries
and an evaluation plan."