There were people locked in the building. Lots of bullets passing through the walls could have killed or wounded them
The shooter claimed to have bombs.
The best solution was a small bomb that would kill him only without killing the other people in the building.
It was an excellent decision.
Bottom line is the DPD killed a bad guy. He was a cop killer.
How well did the ‘bot do in survival?
More merciful than napalm-—with the added benefit you get to use the building again.