The lady that was shot was attempting to enter a hallway through a window while people in the hallway were pointing guns at her. Just because she didn't have a visible weapon doesn't mean she wasn't a threat. Climbing through a broken window into a hallway protected by a makeshift barricade is itself a threatening action. No one at the head of a mob climbing over a barricade ever did so for innocent and non-threatening reasons. Suggesting otherwise is ludicrously stupid.

Having seen multiple videos of the event it's clear the shooter was not firing wildly into the crowd. They were aiming specifically at the person trying to break into the area. She's dead because of her own actions.