Sorry, Big C or not, these questions have to be asked!
What if it had have been your son, brother, father, wouldn't you demand a plausible rational for why your relative come to be beaten to death in a maximum security prison in full view of surveillance cameras?
Plenty of innocent people have died behind bars before having stood before the courts to appeal their sentences, and whilst I have no doubt Carl was guilty of having committed the crimes he was serving time for, this is still gross negligence on the prisons behalf.
If it can happen to an inmate, it could happen to a prison officer.