Of Arms & the Law has covers changes to police tactics that reflect experience with active shooters.
First off, active killers almost exclusively seek out gun free zones. They may be “active” but they ain’t stupid.
Many malls and workplaces also place signs at their entrances prohibiting firearms on the premises.
Now tacticians believe the signs themselves may be an invitation to the active killers.
When confronted with a gun, they usually turn their weapons on themselves. The best target IMHO.
In light of this, the new tactics are that who ever gets there first and is armed, attacks the active shooter.
Good idea… If only we could somehow pre-deploy tens of thousands of armed people to deter and/or stop active shooters. If only…