Already addressed in the legislation. Self defense is sufficient reason in all states (being defined as imminent threat to life or limb of self or other) with the caveat that lesser force is impractical. In Kentucky, catching someone in the act of arson is also justification. Whether someone's illegal presence in your home is sufficient justification in and of itself varies from state to state.Oh, and what bad things justify an armed response? Would you shoot dead a vandal? A mugger? A burglar? What price death?