So any nutball’s boss is responsible for figuring out if he will commit violence and what? Just shoot him as he leaves?
The article says “co-workers”, not “boss”, overheard him making threats. It also states that the USN knew about his history of violence, but did nothing. A dirtbag like that shouldn’t have access to weapons of any kind, and probably should have been in the brig. He was a timebomb, just waiting to go off.