There are many LEO's who are very proficient with guns. I am one of them. YOu would think all LEO's would be, but many are just not interested in guns. I know cops I work with who don't own but maybe one gun and that is usually a .38 revolver. Yet at work they carry the SIG 229, an M4, and a shotgun. But they have no interest.
All LEO's should be familiar with firearms and should be up to speed on modern tactics for LE and military. IF they are not they are doing a diservice to their partners, themselves, and the public. I expect all cops to be fluid with search techniques, building clearing, cover fire concepts, and all modern weapon handling techniques. Our firearms instruction is some of the best on the globe, yet there are some who still don't get a grasp!
I was at the range qualifiying with my M4 and we were shooting on the move. The little fat LEO next to me had no grace, did not groucho walk, and ran while he was bounding with the rifle swinging towards me. I stopped the line and corrected him and put him in CHECK! Unbelievable!
But then you have many guys I work with and a few gals who are fantastic and really get it!
May God make smooth the path you follow!