Except their bad judgement left a man dead.
There is a chance that had they been arrested immidiately they wouldn't have been convicted for murder, or even manslaughter, or anything. The burden of proof is high and maybe they would have beaten the charges.
However the fact that they killed the guy was so blatantly wrong. I mean even if they caught him stealing red handed, which even according to your worst case they didn't, he doesn't deserve to be chased down with a bunch of guns.
But in a sense, what was even worse was that it immidiately got covered up and ignored. If not for the video we aren't having this conversation.
All your taanos may be enough for them to beat a murder charge, but it doesn't change the fact that he was killed unnecessarily, more than likely for being black, and the likes were exonerated without even a cursory investigation.
I am not disagreeing with the fact that they should've maybe acted differently, in hindsight they would most like agree with you.
If you think of it from a perspective of this actively happening it's not to hard to understand why it did.
From the evidence available to the public, I don't see the fact that he was killed because he was black, maybe, happens to be he was black.
Prosecutors are required to
"Generally, the prosecution has the burden of proving every element of a crime beyond a reasonable doubt. But while a defendant isn't required to prove innocence in order to avoid conviction, the prosecution doesn't have to prove guilt to the point of absolute certainty."
Suddenly for the prosecutors to take a 180% turn based on media attention is wrong.
In this case from the evidence publicly available they will have a hard time proving it.