Well, in your line of work, barrier penetration has to be considered.
There is nothing wrong with this line that is your fault. I just want to clarify I am not a LEO. I am departmental staff. I work in the field. I'm usually out there ahead of the cops, with none of the protection.
That being said there are some things that I learned from the Miami shootout that I apply to CCW.
1. Never assume that one shot will be enough.
2. Never assume the sight of a gun will ensure compliance.
3. The human body is an amazing machine with amazing limits.
4. The limits are mental in many ways.
5. Keep fighting until the threat stops.
6. Keep your gun in the holster until you need it.
7. The fight will be what it wants to be. You must adapt to it if you wish to prevail.