I couldn't and someone who would is one step away from Jeffrey Dahmer.
You have hit on something. One of the warning symptoms of psychopathic killers is wanton cruelty to animals as a child.
This person is 24, but you have to wonder if he has a history of such behavior.
It is also possible that it is manifesting itself later in life than usual.
The guy needs serious psychological evaluation as a protection to society.