Cont. from above.
You do not seem to understand what being pinned down actually is, or what continuing to resist actually means.
He was continuing to resist. That is why. They could not get him subdued, that is why. Kelly was also a threat to their safety by resisting.
There were no rouge cops.
If you have to ask "So what?", you are not being objective. The videos are meaningless to this case. Trying to use them as you are is illogical.
Calling them rouge cops is also a sign of your lack of objectivity.
Being on the ground does not mean being pinned down. He wasn't pinned down. Had he been, an arrest would have been affected. His continued resistance says he wasn't pinned.
It is the facts that do not agree with you and actually fly in the face of what you say.
The facts, as well as the Jury decision on those facts, makes that abundantly clear.