> Clearly the guy violently resisted.

Not to the point of requiring a lethal solution. Reaching into your jacket is a no-no when interacting with police, and the grab out of the car was likely fine. Once on the ground though, it doesn't matter how much they're kicking, the gun is only called for if they're going for a weapon.

I'm unclear as to protocol on taser vs gun when an unknown weapon may be in play.