No, they are more selective about taking on contingency cases. Every losing contingency case is hours of unpaid work.
I've sat on a jury for 2 days on a malpractice case that had no factual basis, that relied on a tortured interpretation of medical notes.
We unanimously decided the case for the defendant. Wish we had the opportunity to somehow penalize the lawyer for wasting everybody's time. I'm sure I'm not alone.
The only reason the lawyer took the case was that he was hoping to strike gold, and was a crap enough lawyer that only people who were turned away from better lawyers (because they had no case) came to see him.
Having to pay for the doctor's lawyer sure would have deterred this guy.
I'm pretty sure that this works pretty much like spam or nigerian prince scams. If the lawyer works on tens or hundreds of such cases some % of those cases could be won and some % will settle to avoid legal costs. Total income might be high enough to justify unpaid work on other cases. I'm pretty sure that you could even partially automate a lot of things (or at least use some templates) for multiple similar cases thereby reducing the amount of unpaid work.
What's the reason, and does that reason contravene legal/judicial ethics?
I am suspicious of slang terms like "ambulance chaser" and "jaywalking" that tend to bias the listener in favor of well-funded corporate interests over individual citizens.