OpenAI launches Astra for Law, a legal AI platform with a 230M+ URL legal index

On September 17, 2026, OpenAI announced Astra for Law, a legal-specialized AI foundation platform. Its legal search index spans more than 230 million URLs and integrates the CourtListener case library, which covers more than 99.9% of published U.S. case law.

OpenAI evaluated the system using 200 U.S. legal questions from the private validation set of the Vals AI legal research benchmark. At the highest reasoning setting, Astra for Law achieved an overall accuracy of 54.0%, compared with 38.7% for GPT-6 Astra using web search only. On case-law-oriented questions, Astra for Law identified 24% more reference cases, and in an audited set of target paragraphs, it retrieved up to 54% more relevant paragraphs from correct court opinions.

The service is not an “AI lawyer.” Instead, it is designed for lawyers and legal software companies, helping them separate core holdings from dicta, find adverse precedent, analyze how contract terms allocate risk, and improve case outcomes.