Speaking from personal experience, most Police Officers encounter violent situations an unspecified amount of time in a career, which could amount to 30 years.
The mental and stress related scars cannot be physically seen of course, and in order to deal with the aftermath of situations which have been life threatening, it is very common for Officers to deal with them by using levity which others may perceive as disrespect.
To simply decry and condemn an Officer for such behaviour, hence, is to display vast ignorance of the very reality of situations caused by other human beings which are required to be dealt with by other humans, albeit in uniforms. What must never be forgotten, though, is the fact that no amount of training can adequately equip a Police Officer to be "different" to Joe Public - all of us are mere humans, nothing more, nothing less.
Remember that before making ridiculous and ill informed comment.