A lot of law is combing through large bodies of rule sets and reference cases to find inputs or parallels relevant for a case. Are you sure you'd rather have Lionel Hutz, Esq. with his limited comprehension do that at half a page per minute?
AI can not meaningfully suffer consequences for what it does, and the trend is to remove the human from the loop more and more.
Furthermore, it's entirely conceivable that you have a law firm staffed by lawyers who more-or-less just say "yeah sure whatever" to what this thing does and, when asked about what can be done to appeal something, or how a document didn't make it into evidence, or how a subpoena wasn't filed, just shrug their shoulders and go "iunno". Vibe-practicing law, basically. You need to have an idea of how they're using AI and in what parts of the case.
If merely sounding authoritative is enough to get past a judge, then vast numbers of people are already likely having years of their lives taken for no good reason, entirely without AI. Fix that, and a disclosure doesn't matter.
It's ultimately his name on the documents submitted to the court.