The police union, "The Fraternal Order of Police", vigorously defends its members and advocates strongly in defense of non-member officers (typically rookie cops; reserve deputies; officers who reside in states with "right-to-work" law; and/or individuals who simply have't joined; etc.), to employ the defense of, and with mantra-like committment, "I was in fear of my life." Both states' and the U.S. Supreme Court uphold the general protections of law officers and them with provide broad immunity to 1) use deadly force in self-defense, to wit: "...the officer has probable cause to believe that the suspect poses a significant threat of death or serious physical injury to the officer or others"; 2) as a means of reinforcing the presence of a law officer as a force of deterrence; 3) and, to ensure the viability of the profession of law enforcement as sustainable (meaning, few folks will want to be cops if they think their actions while doing their job may result in them going to jail.).