There is an episode of Behind the Bastards[0] that covers David Grossman, the creator of Bulletproof Training which has trained thousands of police. Grossman’s training involved instilling a sense of fear in the officers which promotes a mentality of fearing for their safety even when it is apparent the officer isn’t in danger. Using made up phrases such as “killology” which Grossman claims to study and using false data (saying it is more dangerous to be a cop now than ever before despite evidence of the contrary). The training materials even use bible verses to justify why it is ok for an officer to kill, even when the situation wouldn’t necessarily warrant even a draw of the gun.
[0] https://www.iheart.com/podcast/105-behind-the-bastards-29236...