Once again, I will say - not every lawyer is ethical in every instance, but the types of situations you are talking about are uncommon, unlikely, and outside the norm.
The fact that a civil suit was successful cannot be used as evidence in a criminal trial because it is too prejudicial, and a settlement would certainly not be open. The opposite, yes, but the presumption of innocence means that a criminal trial has to be resolved on the evidence of the CRIME.
Should a successful civil suit be sufficient to prompt a criminal investigation? I think it can be a reason to prompt a criminal investigation, but again it is very fact specific. Also, in many cases criminal investigations begin and end without public knowledge, because the investigators can quickly conclude that there isn’t sufficient evidence to support a criminal conviction.
There are very few drug dealers who end up in court on civil claims. Drug dealers tend to settle their disputes without the fuss and bother of the judicial system.
I’m not sure it’s much better for victims who win a lawsuit. Different field, but the word I heard when I was in academia was basically, no one wants to hire someone who’s made a sexual harassment allegation, no matter how much evidence they had. It had more to do with the perception of sexual harassment and what comes through the grapevine.
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