Actually it's self defense. They were robbing me and I was protecting my property.
First off, I'm not defending them in any way, shape or form here. All I'm stating here, is simply the action of which you took, from what you have described it as.
There's a fine line between "self defense", to "protect your property" and, I quote:
I beat the crap out of him and his friends along with my best friend.
So no, I don't agree with it being self defense. If you "beat the crap" out of him, it's not self defense. Self defense is when you use the necessary force to protect yourself, or your property, in this case, from being damaged or hurt, in any way, shape or form.
"The right of self-defense (also called, when it applies to the defense of another, alter ego defense, defense of others, defense of a third person) is the right for persons to use reasonable force or defensive force, for the purpose of defending one's own life or the lives of others, including, in certain circumstances, the use of deadly force."
- From Wikipedia (NOT really an reliable source, but just to give an idea of what I mean here)
And if you beat him to death, which is what loosely and basically, "the crap out" means, for robbing you. And not trying to endanger your life, then you went above and beyond that. Which then went into the zone of assault. And possibly homocide, depending now on just exactly how badly you "beat the crap out of him and his friends".
My apologies and sorry, off topic here. Just an explanation of my view on what NBD wrote.
And anyway, I'm out of this now