Unless anyone else has been through two police academies, and has 5 years as a peace officer, let me make a comment here.
1) If the officer had probable cause and arrest powers, he was legally within his powers to arrest the citizen.
+
2) During the course of that arrest, the officer felt his life or the lives of others were at risk, he is within his powers to affect force necessary to save his life of the lives of others, up to and including deadly force.
I could not see if he had a taser on his belt or not, but the conditions of the scene are also something that will play a part.
1) It looked dark and later in the night.
2) He was alone.
3) The subject was potentially drunk or under the influence of a controlled substance.
If he was genuinely afraid for his life, and you could see him taking a few solid shots to the face, you're looking at a justified shooting folks.
He will walk.
Not saying it's right.
When you're being arrested, you go with them. If they illegally detain you, file a lawsuit and make some money. There is never a situation where you fight someone with arrest powers.
Get them in court. It's better to be tried by 12 than carried by 6.
Sad that they guy died. Had he not, he would be facing felony assault charges and end up going to jail, even if he was innocent of the initial crime that the officer attempted to detain him for.
Don't shoot the messenger, I know the law. Many here do not.
Michael, I believe that you were an officer in Florida at one time, so you also know.
**Disclaimer: I only watched the video. After reading some of the backstory. The subject was being placed under arrest for being involved in a fight. So you have a violent crime there that the stop is based on. (Assuming that is what happened, I was not there).