While people can interact with GPT-3.5 and GPT-4 directly, what will eventually be more common is interaction with GPT teamed up with other software. Lexis, Westlaw, and Bloomberg are all developing generative AI tools incorporating GPT while also adding layers both before and after GPT to adjust for accuracy and verification. These legal research generative AI products are designed for accuracy versus ChatGPT which is designed for language fluency. With these added layers, prompt engineering is less important, but knowing generally how AI works, as well as its strengths and limitations, will still benefit the user.
Potential use cases (some of these perform better than others but since these products are still very young it's hard to say which):
More resources
Mohar Chatterjee, How lawyers use AI, Politico (May 2023)
Legal research vendors have worked aggressively to build products that limit hallucinations and increase accuracy. First, most have developed specialized models trained on narrower, domain-specific datasets. The idea is that "good data," and only good data, is allowed in the system. Secondly, most vendors are using retrieval-augmented generation (RAG) which takes the user’s question and passes it through a database that then adds to the user's question as “context” that is then sent through the model. Third, some products may also use vector embedding as a way to identify concepts, by way of assigning phrases or even entire documents, as numerical vectors. Coupled with RAG, this increases precision and relevancy. Lastly but certainly not least, almost all vendors incorporate human feedback on responses.
It is true that these methods have reduced the risk of fake cases as seen in the Avianca case. However these systems may still hallucinate with false sources or produce flawed outputs due to human user error, prompt misinterpretation, or missed issues.
A 2024 benchmarking study indicated that legal generative AI models do reduce errors compared to general-purpose AI models like GPT-4, but that these models still hallucinate at an alarming rate. In fact, the Lexis+ AI system produced incorrect information more than 17% of the time, while Westlaw’s AI-Assisted Research and Ask Practical Law AI hallucinated more than 33% of the time.
Lexis+AI released Lexis Protégé to USD in February 2025, taking the place of Lexis AI Assistant. According to Lexis, Protégé can:
Protégé is trained on both primary law (statutes, cases, constitutions, state and federal rules, and select administrative agency decisions and regulations) as well as a limited amount of secondary sources owned by Lexis (Matthew Bender, certain treatises, and Practical Guidance).
Bob Ambrogi, LexisNexis Launches Protégé AI Assistant to General Availability, Promising Autonomous Completion of Legal Tasks (January 27, 2025)
As of January 1, 2025 all USD law faculty and students have access to Westlaw CoCounsel: Your Generative AI Legal Assistant. Access Westlaw CoCounsel through the law school portal or Westlaw main landing page.Westlaw CoCounsel includes access to several different tools:
A fifth tool, HighQ Contract Express Legal Tracker is currently not available in our academic subscription.
Westlaw account representatives will provide optional training in spring 2025.
Bloomberg Law has launched two new generative AI-powered research tools – Bloomberg Law Answers and Bloomberg Law AI Assistant. Both tools are available to current Bloomberg Law subscribers at no additional cost.
Bob Ambrogi, Bloomberg Law Rolls Out Two AI-Powered Legal Research Tools, Emphasizing Accuracy and Source Attribution (Jan. 30, 2025)
Legal research behemoths Lexis, Westlaw, and Bloomberg are in an arms race to bring generative AI tools to their platforms. For each of these companies the primary concern is "good data in, good data out."
More resources on how vendors are fine-tuning their generative AI models:
The PDF below shows all the legal tech companies currently working on generative AI tools as of June 2024.
