How many times have you thrown popcorn on somebody in a theater? How many of your family members or friends have done so? Doing such is an assault; a crime.
Without knowing more, the evidence would seem insufficient to justify shooting, but you don't have to wait for someone who is attacking you to cause injury. You just have to have a reasonable fear of great bodily harm or death.
What do you think that the attacker was going to do AFTER throwing the popcorn? Just sit down and enjoy the movie? Would he break off the attack and leave the theater? Did he have anything else in his hands?
What was the reasonable thing for the ex-cop to do? Stand there and absorb whatever punishment was to follow the popcorn? Sit down and make himself more vulnerable? Run away and make his wife the possible target of whatever was coming?
The ex-cop was in a place where it was legal for him to be. I don't believe he had any legal duty to retreat and since his wife was with him, retreat may have been a problem. THAT is a "stand your ground" situation.
Is throwing popcorn a felony? Is it a violent felony? What further attack could be expected? Is deadly force permitted to stop someone who has or is about to commit a violent felony from doing so?
“How many times have you thrown popcorn on somebody in a theater? How many of your family members or friends have done so? Doing such is an assault; a crime.”
None of that is germane. The guideline for the use of deadly force is the person using it must be in genuine fear of his life or great bodily harm. Thrown popcorn is a real stretch. Nor did the shooter challenge the other party: “I have a gun, freeze @#$#@@#!”.
The shooter will die in jail, I’d be willing to bet on it. He exhibited very poor decision making. Most likely there should be a yearly exam for CCW after 65, just as there should be for driving.
The sheriff takes issue with your histrionic description of the encounter:
‘Why didn’t he just sit somewhere else?’ Sheriff rips apart ‘Stand Your Ground’ defence of ex-cop who shot dead father for texting in movie theater
http://www.freerepublic.com/focus/f-chat/3112725/posts
You also need to take into account the other theory of the popcorn, which is that the popcorn flew into the shooter's face at the moment the bullet impacted the unarmed victim's chest and not before.