I've often discharged my ML to unload, but 2 1/2 hrs after dark seems kinda long. I guess if they were near houses when they did it that would be a no-no, I always did mine back away from anybody and just shot it into the ground 10 ft from the muzzle.

Knowing they were massively baiting against the law, they probably weren't unloading but were shooting at game in the moonlight or something.