I have a pal who is a serious rider, i.e. he races on the side (has a different day job). Years ago, over a period of weeks he was harassed repeatedly by the same driver in the same pickup truck (pal got his tag number early). One day this truck comes by with 2 passengers, buzzes my pal a bunch, then throws a full beer bottle at him. The bottle smashed on his head and he wiped out like
the Agony of Defeat skier. Truck stops about 30 yards ahead while my pal is laying in the road, seeing stars from the crash.
All 3 guys exit the truck and 1 has a baseball bat in his hand. They loudly explain that they are going to completely f**k up my pal. So my pal draws a little .22 pistol he had been toting for this very situation and warns them to stop or he'll shoot. They keep advancing, so he shoots one of them. The bullet hit the guy's femur, broke it and he dropped right there. The other 2 run back to the truck and skedaddle.
All 3 got convicted. The 2 most violent ones went to prison and the 3rd guy who "was only driving" got lots of community service and monitoring.