I don't want to get into too much detail about my old job but basically I was in California criminal court rooms a lot, in 5 different cities over 14+ years so I speak from some experience. (For me it was adult court and mostly drug, violence, & gang related stuff but I think what I'm about to say still applies.)
I think the real problem is the writing. The lawyer won the case for client so there's that, but she did it in a way that would have been basically impossible IRL. The witnesses she called, the questions she asked, the things she knew that she had no possible way of knowing, most of it was completely irrelevant to whether THE SCHOOL was responsible for Hannah's deaths or not. I said the same in a different thread but I'll repeat it. Had this been real life, Hannah's lawyer would have been going "Objection your honor, relevance?" every two seconds.
Her attitude, condescending tone, facial expressions, were just designed to annoy the shyt out of the viewer. IRL that kind of behavior can annoy the shyt out of juries too and cause them to vote a certain way just because they hate the lawyer so much so the lawyer has to walk a thin line between choosing to use psychological microagression tactics to psych-out the witness but also not be a fukking grinch about it to the point where everyone can see right through her. People make fun of lawyers like that, like that they must have just graduated law school and learned how to behave in a court room from watching TV and don't have much IRL lawyering experience.
Bryce's courtroom scene was pretty realistic though. They don't really make it too clear but he WAS found guilty, and that was just his sentencing hearing. I was surprised however that he was either not put on the sex offender list (which I'm pretty sure is mandatory with a guilty verdict) or that the show chose not to mention it. I like how they contrasted it with Justin, the poor kid, getting screwed and punished worse than the actual rapist, however he DID have both Clay's fancy-lawyer mom and Hannah's parent's lawyer defending him so that was weird. I would have thought they could have done much better for him and that they would have known all the way from the beginning about him being a minor and only being released to a guardian. They should have started the emancipation process for him or found him a legally appointed guardian and not waited until the last second.
What happened to Justin was more like what would have happened had he had a public defender assigned to him that had zero time for him because s/he has like 20 other clients. What I'm trying to say is that he should have gotten off, but I think 13RW was trying to make a point about how rich kids get off and poor kids don't but they did it in a pretty unrealistic way that crumbles apart when you look closer. Actually I'm not even sure what he got convicted of? Accessory to rape? Apparently he plead (either guilty or no contest to something, but to what??) And why the fukk would they let him plead like that? They should have gone the "not guilty" route all the way from the beginning. Even if Bryce was found guilty of rape, two bright lawyers could have still gotten Justin off as not guilty of being an accessory (or whatever it is he was charged with.)
There was a case in California maybe 25-30 years ago where a grown man grabbed a little girl and raped her in a gas station bathroom and his friend just stood there and did nothing to stop him or go get help, like he just stood there like a tree, not participating at all, and he got off because it turns out there was nothing in the law requiring that he do anything. The prosecution I think tried to twist it like he was standing guard and try to nail him on that, but even that was thrown out. So just using that case as a precedent, Justin at least fought with Bryce and tried to stop it. This was just stupid.
So yeah back to your original question, she was a joke. But Clay's mom and Hannah's mom's lawyer was an even bigger joke.
And why didn't Hannah's mom's lawyer ever bring up that ANOTHER STUDENT, Alex, also tried to kill himself? This school has a track record of two suicides attempts by students in one semester, clearly that's a red flag.
I think the 13RW team should have consulted with actual lawyers on this courtroom stuff. If they did, then they didn't listen to what the lawyers had to say because I can't see any lawyer giving a thumbs up to how the writers depicted things.