Frankly, what I’ve seen of cops after they shoot someone, or being the first to cop to a bar shooting, or even when being the first cop to a death in a house, they seem like deer in the headlights, awkward, unsure, and hesitant yet wanting to appear as dignified police, they are easily shaken.
Every individual has their own “wig out” stress threshold; and the individual’s behavior is unique.
There are varying degrees of “the when of it” and “the performance” that may be trained to delay the moment and modify the performance.
There are varying degrees of success, in such efforts. Some people are able to leave the trauma, shock, and awe . . . behind. Some people.
A friend of mine, was among the initial combat surgeons on Guadacanal, at Henderson Field.