“In 2012 alone, police officers, security guards or vigilantes took the lives of 136 unarmed black men and women — at least twenty-five of whom were killed by vigilantes. In ten of the incidents, the killers were not charged with a crime, and most of those who were charged either escaped conviction or accepted reduced charges in exchange for a guilty plea.”
The American justice system worked the way it is designed to work and the design is seriously flawed. Unfortunately, they way it works is heavily weighted against a significant percentage of the population. In Florida, you can shoot to kill even if retreat is a safe and viable option. Zimmerman was allowed to claim self defence even though he provoked the confrontation.