[kiryandil]

What it means is that if you have a suspect who has committed a felony — like assaulting a police officer — and is dangerous, you can shoot him as he flees in order to keep him from endangering other people.

If the police officer, Slager, was assaulted, it appears to me that he created the conditions for the assault by seeking confrontation with Walter Scott at all costs.

Slager had Scott's details, his car, and his passenger.

Why did Slager seek out a confrontation?

I mean, what you're saying is that all I would have to do is get in your face till you swung on me, then you're my meat, in whatever way, shape or form I choose to dine on you...

Slager is either dense, or he's a predator.

[Yardstick]

Every time a policeman initiates an arrest or pursues a suspect it is in some sense “pursuing a confrontation”. That’s what we pay the police to do.