When Questioning Goes Horribly WRONG

I saw a former student sitting alone looking down. I asked what was wrong. (Mistake! I was hoping he was waiting to go to the restroom or was just sad...but that would've been easier than the sh!tstorm that followed.)

"I got put out by Mr. Blank because he said I was-"

Another adult then jumps in...
He continues to explain himself. I feel bad that I even asked and attempted to address the matter. 

"You've been working so hard to do better. Don't make bad decisions. Mom has been supportive. You don't want to embarrass her or yourself after you try and do right then make a bad decision that changes what you're working towards." I say.

Immediately another adult jumps in, followed by another adult addition, which only heightens the situation and consequently antagonized the situation. 

"I know what I'm talking about...(the student goes on a tangent demonstrating what he did explaining his two uncles whom were in the army do it and he was doing it too..."

The adults disagree.
He BLOWS up! 
Next thing I know he's being suspended for banging on the walls, turning over tables, and hollering obscenities as he paces the halls like a rabid dog having stare-offs with the teachers.