How is rape and murder an issue of chain of command issue? It's a basic issue of knowing right from wrong. Are you saying that unless supervised, troopers will default to savagery? A five year old knows this behaiviour is wrong.
If this guy was a mental case, he shouldn't have been permitted to have a weapon, PERIOD.
If this guy was intoxicated, he shouldn't have been in possession of a weapon, PERIOD.
This is a Chain-of-Command case. Where were they? Why wasn't an NCO there to beat this guy over the head and reinforce the point that his actions are not condoned (if the accusations are true).
When I was an NCO, we constantly monitored our troops, on and off duty. We were responsible for everything our troops did, or did not do.
It's called Leadership. That's what the NCO Corp stands by, regardless of the branch of service.