There are two aspects to our legal system: criminal and civil. While hate speech is considered protected and not prosecutable under criminal law; it can be adjudicated under civil law.
If a rapist is tried and convicted of rape, and said rape is atribituted to this man' author's writing, the author can be successfully sued in civil court
If a rapist is tried and convicted of rape, and said rape is atribituted to this man' author's writing, the author can be successfully sued in civil court