Im just putting myself in the position of a member of the family of the deceased / injured. Imagine an acquaintance who happens to be a pilot says, I will take you on a a fly around the region. The pax have no concept of what is illegal, dangerous or otherwise in terms of light aircraft operation. They are putting their faith and lives in the hands of someone who should have known better.
So if a criminal conviction didn't stick for whatever reason, what would be the family's recourse through civil action?