This scene has two sources of inspiration.  The first was derived from a photo appearing in an historical series book which dealt with crime and punishment in the USA.  The photo depicted a man, facing away from the viewer. He was stripped to the waist and grasping the cold steel bars of a jail cell.  A uniformed guard was positioned behind him brandishing a leather strap.  It was up to the reader to imagine what was to come.  The second source is the jail house whipping scene from the Clint Eastwood Film "The Unforgiven", in which the actor Morgan Freeman is whipped to death by the sheriff portrayed by Gene Hackman.