"What do you consider an active ongoing threat? My viewpoint is a fleeing suspect isn't an active ongoing threat, but you might consider otherwise."
I would disagree because, depending on the situation, If the BG posed enough of a threat to YOU to justify shooting, even if he runs away, he will likely present just a serious a threat to some one else. (obviously this probably would not apply in a case like domestic abuse, or other instance were the motive is "personal")
"Oh, as a side note here's something I found amusing about LEO and DAs. When describing incidents LEOs say things like "the suspect struck the victim". DAs describe the same incident as "the defendant struck the victim." It's a small thing but speaks volumes about the difference in viewpoints between them."
The Police have to go by the "assumption of innocence" so any Identification of the BG has to be proven, (even if the victim gives the attackers name, It COULD have been his twin brother, The Police don't know. and the whole point of a trial is to prove whether or not the "suspect" is in fact "the perpetrator")
While the Prosecutors job is easier, the person at the other table who isn't the Lawyer, is only there to DEFEND, against an "accusation", which regardless of the results of the trial, makes him the "defendant".
It boils down to semantics.