I would take a peek at your local "dangerous dog" laws. Laurel went through a bitey phase and it helped me a lot to know exactly what the laws are.
If somebody abuses my dog and she defends herself before I can protect her, the human is at fault according to the laws of my area. I would fight it in court and win, although not for the reasons we might want.
Laurel: born 9/1/18, 7 lbs, my homegrown
Chocolate: born 10/4/18, 9.5 lbs, rescued from DV situation