The first rule when confronted by a police officer is - do exactly what he/she says. I won't be resisting arrest in any manner. We'll sort out possible unlawful arrest in court, not on the street.
I have a suggestion: Spend an evening riding with a police officer in your town (most departments offer "ride-along" opportunities to citizens.) Watch what the officer has to deal with on his shift. You will be amazed at how much bad behavior he/she encounters by "upstanding"citizens, let alone the scum who clearly have done something wrong.
I believe you will conclude that police officers are seriously underpaid, patient, professional people who typically don't over-react even in dangerous situations. After your ride-along experience, let's discuss this again.
While this seems to indicate perfection on the part of the police, civil court actions or settlements amounting to multiple millions of dollars have been awarded to the survivors of some of "justifiable" deaths.
Knowing only what I read above about this case, I find it amazing that the gun was "thrown" thirty five feet as described--