In Texas a police officer may shoot a fleeing felon. If the perp fought the officer then that is a felony and on that basis alone, the shoot was legally defensable
But this was in South Carolina.
In the real world, the only real reason to use deadly physical force, absent a Castle Doctrine (which is no longer operative in some areas) situation is to save yourself or someone you know from death or grievous bodily harm.
Never assume who the bad guy is.
Abut 40 years ago in DC, my friend’s brother was an off-duty rookie cop, 17 days out of the Academy. He comes out of a building in midtown Manhattan and sees two street scum pop out of a rolling wreck and jump on a silver-haired guy in a $2000 suit.
He draws his weapon (a .38) and screams for them to stop. They do not. He within half a second of firing when, simultaneously, three more guys, two looking like street scum and another looking like an Orthodox rabbi hop on the well dressed guy and another street gut hits his arm up.
Bottom line. They were all NYPD and BNDD narcs and the guy in the suit was a heroin smuggler’s bag man, and he had all the past 18 months records on him.