As I understand the law: If it is self defense then the person is responsible to rurn and try to get away before using any force. If "Stand your Ground" all the person has to prove is they were being threatened and they have a right to stand where they are and defend themselves (e.g. they do not have to run away).
The other considerations are the attempts by some, (we know who they are) to try to make this a "racial" issue. Under the circumstances that is dispictable.