When a name is too close to reality.
How do you avoid defamation actions from readers whose real names and circumstances you have (in all innocence) ascribed to your villains?
#1: Portray your most odious characters as Suffering, Complex and Misunderstood victims of circumstance. Not only might this take the edge off any imputation of malice in your alleged defamation, it is also – in these post-Freudian days – good novelistic practice.
Even Hannibal Lecter was a decent fellow in his youth, the author tells us. He went mad only after witnessing an unspeakable atrocity. Without that explanation – and saddled with the name of Hannibal – he might not have been either believable or terrifying.
#2: If your conscience demands that you vilify a real celebrity eg. Bill Gates (oh, but must you, really?), make it clear in the story that your villain can not possibly be Mr Gates. How? Have the villain appear on a conference platform alongside the real Mr Gates, who is agreed by everyone to be a very nice fellow. Obviously, they cannot be one and the same person.