This kid is the epitome of a spoiled brat. From the little background that we get from his brother at the beginning of the video, we're able to gather that Steven is pissed at his mom because she wouldn't buy him the video game he wanted. Steven then decides to go all Zane and break something because he's pissy. In this instance, the family's $3,000 television was the victim. Mom called the cops because he was being such an a-hole. The video picks up when the cops arrive.
This obviously isn't an isolated incident either. You can tell because of how quick the brother is to explain the scenario, as if he's done it a hundred times before.