Thomson Reuters Unveils CoCounsel Legal AI Platform

Thomson Reuters launched CoCounsel Legal on Tuesday, a unified AI platform that integrates research, workflows, and document management for legal professionals.

This launch represents Thomson Reuters' most advanced AI offering to date, moving beyond traditional copilot tools toward AI that can manage multi-step flows across litigation, transactional work, and regulatory analysis. The platform addresses the fragmented nature of legal work where lawyers previously had to toggle between multiple platforms like Westlaw, Practical Law, and case documents.

Deep Research: AI That Reasons Like a Lawyer

The centerpiece of CoCounsel Legal is Deep Research, an agentic AI feature grounded in Thomson Reuters content and tools. This capability enables lawyers to delegate full research tasks to an AI that reasons, sources, and explains its logic.

Deep Research draws on Westlaw's structured legal content to execute multi-step research plans and produce citation-backed outputs. It uses features like Key Numbers, KeyCite, Cited With, Precision Research classifications, and statute annotations to surface relevant cases and identify related authorities.