And this is a point that I think some of you are missing. The more times the accused is vindicated by audio/video evidence, the more widely the whole group are viewed as ethical professionals by the general public (there will always be rabble rousers). The way things are right now, there isn't much trust by a large portion of the public.
That only happens if the media releases the video when the police are exonerated.
They don't.
Maybe you missed it, but no one needs "the media" to release anything these days. Besides - I think we are not far enough into the use of such devices yet to establish any such pattern. If we were, those cameras would have been rolling.