First, always assume the firearm is loaded.
Second, check to ensure the firearm is not loaded, and if it is, make sure it has the right ammunition (blanks for on set).
Third, know your target and what's beyond it.
Last, never point it at something you do not intend to kill.
So either he doesn't know about guns, which 99% of people who are against guns don't.
Or he INTENDED to shoot them.