I've not commented here yet because I am heartily sick of the 'Trial by YouTube' nonsense that has sprung up in recent years.
The bare bones of this incident is that a minor was caught by a police officer doing what he shouldn't. Rather than be senible and "Yes sir" at appropriate times and go on his way with a warning, he chose to what we in England would call 'use his cheek'. The officer gave him what-for and quite rightly so.
Law enforcement is not an option and respect (aka appropriate level of fear) of those in uniform is likewise not optional. We've let that go lately and it's a part of the price we're paying in social misbehaviour.
Without being too dramatic, the social structure is cracking under our feet even over here in civilised ole England, with 'teens (the bad ones) running amok with no respect for authority or fear of reprisals.
To give an example from my life, my father, who is in his seventies, has only one leg and walks with crutches these days, had trouble with a gang of 'teens pelting our house with eggs and other sundry garbage after he told them to stop sitting on our lawn. He goes out to talk to them, receives a verbal threat accompanied by physical encroachment to which he responds with a commendable lack of fear and derision to the courage of a bunch of youths threatening an old man.
Guess who got a visit from the cops? This sort of madness, wherein the young are not shown that to step out of line has costs, has to stop or when we grow old, if we get the chance, we shall be cowering prisioners in our own homes.