you are licensed to carny and have a legal weapon. a shooter in a crowd starts firing. you pull your weapon and return fire and hit the shooter but also hit a bystander, can you be charged with hitting the bystander?

yes depending on the Prosecuter.

That might depend. If you are a person who believes in personal responsibility, and supports laws in that direction, then you could be prosecuted.

If, on the other hand, if everything that happens is somebody else's fault; especially if the bullet grew up in poverty with only a single parent, then you're home free.

I would, seriously, say that when you pull the trigger you are responsible for where the bullet ends up. Which is why, if you intend to carry in public, or use a weapon in self-defense, that you should have some training in not only the use of the weapon but the responsibilities that accompany it.

Too many variables.

You may or may not be charged with a crime, but you will be sued into oblivion in civil court.