There's a lack of discipline in this child's life and it's quite evident through his behavior and lack of respect for his mother. The problem starts higher up, I would bet the farm that mom hasn't won any parenting of the year awards herself. Sure, he needs his ass beat and at his age he should know better. If the child had a better understanding of what respect was and had he been shown the repercussions of not showing it he wouldn't be acting this way.
just my 02..
I agree, alot kids these days don't have a clue what the words respect or consequence mean.