a. it wouldn't be an anarchist state. it would be an anarchist area.
b. there are many questions here about crime and punishment, and how they would be addressed in an anarchist scenario/situation. you might want to search for the tag "crime," etc. the answers run in the direction of... it would depend on specifics.
the premise here being that there is not a generalizable "drunk driver" who hits "somebody". there is a person with a name and a history and relationships, and those would come into play when people were deciding what to do with this person.
also, i'm fond of rats.