A large corpus of documents does not have to mean privileged info. Put all of the public documents from a case in there and ask it about a judges reasoning.
Honestly that wouldn’t be a terrible product: Pull in all of a judges written judgements or stated logic about their rulings and preemptively craft your case around their biases.
AFAIK no state level organisation has sanctioned someone for this. You can opt-out of data collection, which some practitioners think is good enough to satisfying their professional liability- risk tolerance depends on the individual (this is not advice, just my observation!)