There is no doubt that these gatherings are a nuisance to the neighborhoods. The problem is that no law is being broken by the kids being there.
The cops need the permission of the property owners to run the kids off, which they may or may not have had. If they do have the permission, and the kids refuse to leave, then they may be arrested for criminal trespass. But they have to be given a chance to leave.
If there is a fight or something like that, or if motorcyclists are doing wheelies and are being loud or dangerous, an arrest could be made for disturbing the peace. That is what the police should have focused on.
But there is nothing illegal about people getting together on private property and having a good time, which is essentially what was going on here.
Apparently, police believed that these gatherings preceded some street racing, and this was sort of a staging area. Stopping street racing is an appropriate police function. But what they should be doing is patrolling the places where street racing occurs and stopping it there.
I have sympathy for those people who have their homes or apartments adjacent to these parking lots, but it essentially comes with the territory. If they don't like it, they should move to a quieter neighborhood. Anybody who lives within a block or two of Westheimer needs their heads examined, anyway. The street is a madhouse, especially on weekends.
Not to continue a silly argument, but I respectfully disagree with you here. I am quite sure the cops have the right to disperse a crowd the size of the one in question. No, I can't point to the specific law, but the cops do not need the owners permission to disperse a large crowd that is obviously not invited to be where they are.
Many of us simply wish "cops" would use common sense in many situations instead of "just following orders". Well, I think its common sense that a crowd of 400+ was not invited to hang out in a parking lot at 12:30 am. Arrest them? No. Hand out citations if its known that this crowd comes there week after week? Yes. The kids do not have to be told not to come there and hang out. They know they are not suposed to. That's common sense.