From what I've read your last statement is completely wrong. Cops are trained to shoot even if the suspect has a pair of scissors in hand, within an estimated 20' distance, probably after demanding to drop the weapon. They are definately not trained to shoot only after being shot at.I don't know the details of the case, but would like to make a general point that may apply here.
Cops need to be trained on how to use non-lethal force, hand to hand combat and tasers will do the trick.
The only time a cop should be shooting is if he is being shot at. That is how they are trained.