On the other hand you inexperienced, untrained simple Simon, its not like the shooter was wearing mismatched military gear, a balaclava and firing an AK-47. He was wearing a US Army uniform like most or all of the others there and firing a sidearm the type of which the officer may not have recognized at first. For all you know, the officer may not have known if he was a bad guy or a good guy who happened to have the ability to defend the others and was trying to take down the bad guy.
Maybe telling the shooter to drop his weapons and identifying oneself as a police officer was more appropriate than you thought.
You weren't there and you don't have the whole story yet.
How would you like to be a citizen with a legally carried firearm who is trying to defend yourself and fellow citizens during a terrorist or criminal attack, and have the police shoot you down without giving you a chance to explain yourself?
Sgt. Mark Todd and Sgt. Kimberly Munley both heros and both will be remembered in this household as those who brought this piece of work down.
Could also be necessary as a legal requirement for court.