Up to now it's been an article of faith that crazed gunmen looking to set a new high score, don't normally make their attempts in police stations. We has one here in Colorado some time back in which a fellow pulled up in front of the Castle Rock PD building and opened fire toward the building. As I recall, no one in the building was hit, and even though the fellow had his 2 small children with him, it ended about like you'd expect.
The thinking was that he didn't really expect to kill anyone in the building.
Someone has tried again, this time in Detroit, where someone walked in to the station with a pistol-grip shotgun, and began blazing away. No real details out yet, but 4 cops were wounded and the shooter is toast.
Quick! What should we ban now?