"In December 1959, shortly after the Castro victory in Cuba, I attended several of the trials of war criminals conducted in the Cabaña fortress of Havana, in the course of which I was subjected to an extraordinary encounter with Herman Marks, the American who had become the Cuban executioner. Marks spent some time justifying his activities and expounding his personal philosophy, in the hope that I might help to rectify his image 'in the world's eyes'. I suspected that his Cuban employers only saw him as a painful necessity. A year or so later a friend visited Cuba with the intention of writing a book, and included Marks in a list of persons he might find interesting to see. When he returned I asked how the meeting had gone. His reply was 'I was too late. They'd already put him up against the wall'"
Norman Lewis, Fidel's Artist