Somone had called in a report that this kid was growing and selling pot at his house. It was a 2or3 AM raid. The kid was in bed sleeping with his tv on, his dog started barking, his door was kicked in and a guy with a gun was framed in his doorway with bright lights shining in. He shot twice, blindly, and ended up killing a LEO that was outside in the yard. There was less than an ounce of pot, no plants. He had been broken into and threatened a number of times before this by local gangs.
You forgot to mention that the cop was working undercover and dressed as a homeless derelict/meth-head complete with long hair and a scraggly beard.