I guess that's what the people who are suing are alleging. Like if we imagine they did severely fuck up, and it led to a defendant losing the case, then suing is probably the only way you'd be able to get formal acknowledgement of that fuck up.

I think it sucks from that angle too, because as someone who has had to litigate against an organisation, it really sucks to have to do, especially when you know you're in the right.

There's the opposite when there's too much protection: defendant provides an independent expert's opinion, court provides state approved expert of questionable ethics and professional qualifications but with a correct opinion, i.e. the one that supports the prosecution. And guess who the court will listen to, and that state provided expert is untouchable and has no reason to actually do a good job.