> it seems like for law specifically all relevant facts will be cited and checked easily by humans.

Don't be too sure about that. [0]

0: https://www.damiencharlotin.com/hallucinations/

> all relevant facts will be cited and checked easily by humans

I've talked to a lawyer about how they handle this. They do indeed double-check everything, since it'd be embarrassing (or worse) to send hallucinated statements to opposing council or to the court. They still find the assembly a huge time saver

But based on stories in the news on the subject, not everyone has this same level of diligence

Sure but just like generating 100x more code, someone has to review it. So you are wasting everyone in court's time (defendants, prosecutors, judges, staff) by making them parse through what is quite often a bunch of hallucinated slop. Time that could be much better spent on parties who prepared and reviews their own arguments.

The lawyers I know are very fixated on the problem of hallucinated case citations which is amusing to me as a onetime programmer, since case citations have a well-defined syntax and would be relatively easy to check programmatically.