Do you think this is a valid defense, and do you consider this justice?

This is the bigges crock of crap that I have ever heard of. Affluenza? Really? If it were my son, of course I would do whatever I could to protect him, but... what about the people he killed? They have no voice in this.

Since the accused is a minor, the question in the civil lawsuit is whether the parents are culpable and subject to damages being awarded the plaintiffs. The question won't be who did what, but rather what did the parents know and do about it.
The parents were wise to settle, because they were very vulnerable to civil liability. Now for the other three families...

As for the teen who did it, it is hard to say why he was only sentenced to treatment and probation, as if all he did was DWI. Four people are dead.

Hi, Sergeant Jones.

It should not be a valid defense, nor is it justice. A decade of probation for killing four people (at least four counts of involuntary manslaughter) in a drunken stupor? It's an insult to his victims and their families.

That he was unwilling to insist on a much harsher penalty that he knows he deserved makes him a coward.