Sociological Images has a terrifying graph that documents racial disparities in justifiable homicide verdicts
Before I go any further, I want to stress that while this graph focuses on "Stand Your Ground" laws, contrary to popular belief that law was not the primary player in the Zimmerman trial. This graph is instructive not because of what it says about SYG specifically, but rather because of it what it documents about racial disparities generally.
That being said -- this is a scary graph. White-on-black homicides in all jurisdictions are far more likely to be considered "justifiable", but the disparity skyrockets where there is a "stand your ground" provision. What's more, blacks scarcely benefit from SYG at all, at least when the victim is White.