Robert Ambrogi Blog
Two months ago, at a media briefing in its New York City offices, Thomson Reuters teased the launch of the “next gen” of its CoCounsel artificial intelligence platform, marking what the company said would be a fundamental shift from AI assistants that respond to prompts to intelligent agentic systems that can plan, reason and execute complex multi-step workflows within professional environments.
Today, making good on that promise, Thomson Reuters launched CoCounsel Legal, a new platform that combines agentic workflows with deep research capabilities, all grounded in Westlaw content, which the company positions as the most comprehensive artificial intelligence solution for legal professionals to date.
Today’s announcement, which was previewed to the media during a July 24 press briefing, introduces two primary innovations: guided workflows that handle multi-step legal tasks and Deep Research, an AI system that conducts comprehensive legal research using Westlaw’s proprietary research tools.
As part of today’s announcement, Thomson Reuters is also introducing a new version of Westlaw, called Westlaw Advantage, that Thomson Reuters says will now be the final version, capping a history that has seen the platform morph from Westlaw to WestlawNext in 2010, Westlaw Edge in 2018, and Westlaw Precision in 2022.
AI That Thinks Like a Researcher
For legal researchers, the centerpiece of today’s launch may be Deep Research, which Thomson Reuters describes as the legal industry’s first professional-grade agentic AI research capability. Unlike traditional AI-assisted research that summarizes search results, Deep Research creates research plans, executes them iteratively, and delivers comprehensive reports with transparent reasoning.
“What if legal professionals could hand off complex legal research to an AI that could work like their most diligent associate, never sleeping, never missing a citation, and delivering comprehensive analysis at a fraction of the traditional cost?” said Rawia Ashraf, head of product for CoCounsel transactional and GCO, during the briefing. “We know that that’s always been the dream, and it’s not theoretical anymore.”
Mike Dahn, SVP and head of Westlaw product management for the U.S., U.K., Canada, Australia and New Zealand, said that Deep Research goes beyond existing AI research tools by instructing AI agents in the use of Westlaw’s exclusive research toolset, including Key Numbers, KeyCite, Precision Research markup, and statute annotations.
The system can analyze entire legal questions rather than just providing quick answers, delivering reports that include arguments on both sides of legal issues, relevant case law analysis, and related legal questions for further exploration, he said.
The Deep Research system generates multi-step research plans that users can review before execution. It then produces comprehensive reports that include sections on arguments typically made in support of and against legal positions, cases where similar claims have succeeded or failed, and related legal issues that might be relevant to the research question.
Guided Workflows
CoCounsel Legal introduces guided workflows designed to handle complete legal tasks rather than individual prompts. These workflows combine practical legal expertise with AI capabilities to guide users through multi-step processes such as drafting complaints, creating employee policies, and conducting jurisdictional surveys.
During the briefing, Ashraf showed how the system can locate documents across multiple repositories, including document management systems and cloud storage, then use those documents to generate complex legal filings like SEC Form 8-K reports.
The workflow walks users through the necessary steps, provides links to relevant Practical Law resources, and produces first drafts that users can then review and refine.
“These are proactive agents that you can trust because they’re based in our content and your content or a lawyer’s content,” Ashraf said. “And we’re really taking the vision from a copilot to a collaborator, from prompting to delegation.”
The guided workflows currently include capabilities for drafting privacy policies, employee policies, complaints, discovery requests and responses, and deposition transcript reviews. Thomson Reuters plans to release new workflows incrementally, with the eventual goal of allowing users to create custom workflows that the AI agent can execute.
Integration with DMS Systems
A significant technical challenge addressed by CoCounsel Legal is integration with law firm document management systems. Jean O’Grady, a legal technology analyst participating in the press conference, pressed Thomson Reuters executives on the practical implementation, noting that large law firms often have millions of documents in their systems.
Ashraf explained that the system uses federated search rather than indexing all documents. When users search across repositories, CoCounsel Legal leverages the underlying search systems of each document management platform, then applies AI for re-ranking and summarization to make results more interpretable.
“We take the user search and then we add,” Ashraf explained. “We use a large language model to improve that search. We send the search to the underlying document repositories. We get the search results back and then we apply AI for the re-ranking and summarization to make the results more interpretable to the user or to the agent.”
Launching Westlaw Advantage
Alongside CoCounsel Legal, Thomson Reuters is launching Westlaw Advantage, which TR said is the most transformative update to Westlaw in several years. The new version includes an enhanced version of Quick Check, now called Litigation Document Analyzer, which provides more comprehensive analysis of legal briefs and motions.
The upgraded analysis tool can identify arguments in opposing motions and suggest counterarguments with supporting legal authority. It also includes a language analysis feature that examines entire briefs for potential mischaracterizations, going beyond the quoted sections to analyze every legal assertion and compare it against the cited source material.
In the briefing, Dahn demonstrated the use of this tool to analyze a sample motion to dismiss, showing how it identified seven arguments in the motion and then showed the counter-arguments and supporting cases and resources applicable in the particular jurisdiction.
“This is a big deal,” Dahn said. “We’re now doing most of the research work for the opposing motion that we want to file.”
The system also includes a hallucination checker designed to identify citations that may not be real, addressing concerns about attorneys using consumer AI tools that sometimes generate fictional case law.
The Final Version of Westlaw?
Along with today’s technology announcements, Thomson Reuters revealed a significant shift in its commercial approach. Raghu Ramanathan, president of legal professionals and government at Thomson Reuters, said that customers purchasing Westlaw or other AI solutions will receive automatic access to future upgrades without requiring new commercial contracts.
Related: New President of Thomson Reuters Legal Segment Says Industry Needs Open Benchmarking on Gen AI.
“It sounds a bit dramatic, but there may not be any future releases or updates of Westlaw, because what we are really saying is that when customers buy Westlaw — or for that matter any of our AI solutions — they are getting by default access to all of the upgrades going forward.”
By moving to this more traditional Software-as-a-Service delivery model, Thomson Reuters is departing from its traditional approach of requiring new license agreements for major feature updates. The company indicated that the new Westlaw Advantage announced today is likely to be the final versioned release of Westlaw, with future improvements delivered as continuous updates.
Investing Heavily in AI
Throughout the briefing, Thomson Reuters emphasized why it believes it is uniquely positioned to delivering agentic AI for legal professionals, citing three key advantages: advanced reasoning models, comprehensive legal content, and expertise from thousands of domain experts.
The company says it has invested $10 billion in capital to transform legal technology foundations, with over $200 million annually dedicated specifically to integrating AI into flagship products.
“Our agentic AI goes beyond what others are able to offer as they simply do not have the breadth or depth of content, nor the vast pool of Practical Law editors creating and maintaining comprehensive legal workflows, that our customers can trust,” Ramanathan said.
Westlaw Advantage will launch Aug. 13, with most Deep Research features available immediately. Some capabilities, including enhanced filtering options and a questions feature that provides follow-up research suggestions, are scheduled for release in September and October.
Thomson Reuters reports that over 20,000 law firms and corporate legal departments already use CoCounsel, including the majority of Am Law 100 firms and top U.S. courts. The company serves 100 percent of Fortune 100 companies and 97 percent of Fortune 1000 companies, it says.