Evil needs a face and it doesn't look like your neighbor—or your child. Evil must be inhuman, other. The familiar is innocent. We let our guard down. This is part of the diversity paradox.
In the 29 states that use the law, stand your ground increases the likelihood of a justified homicide ruling—but only when a white person is accused of killing a black person.
If you control for developing countries and South Africa, with its history of apartheid and ethnic conflict, there is a strong link between the number of guns per capita and gun-related homicides in a country.