The ostensible motive was robbery. And they found a fall guy, someone to arrest. Well, that should appease the public's need for closure to the case.
But note that victim was tortured for an hour before he died. Did I mention that Angels can be devastatingly ruthless? This makes me wonder if the victim betrayed them. They reserve a special place in hell for traitors.
I must admit, I'm not entirely sure why this particular event has captured my interest. So I'm just filing it away here for now.