Cops RUSH Active Shooter - YouTube
I think this video does a better job than I could of relaying what I would safely assume is a majority opinion among law enforcement. We actually studied this incident and others during our CQB and Active Shooter training. The commentary is on point
My key takeaways (generalized):
-Patrol Division will almost always be first on scene, and patrol officers and deputies are not equipped to the level of SRT/SWAT. This has very meaningful impacts on tactics.
-The odds that even one responding officer has intimate knowledge of even part of the facility is very, very low. You are likely going in completely cold for building layout and the presence of subjects on site.