J. D. Salinger's 1951 novel, The Catcher in the Rye, is widely regarded as an American classic. Catcher, which is still protected by copyright, tells the story of a sometimes disillusioned 16-year-old, Holden Caulfield. The Caulfield character is one of the best-known characters in modern fiction. After achieving great commercial success with Catcher, Salinger wrote very little for publication and acquired a reputation- perhaps not entirely accurate-for being a recluse. He vowed never to write a Catcher sequel or to do anything more with the Caulfield character. Without Salinger's permission, Fredrik Colting wrote a novel titled 60 Years Later: Coming Through the Rye, in which he utilized the Caulfield character but made him 60 years older. Colting's novel about a 76-year-old Caulfield borrowed not only the Caulfield character but also other details from Salinger's copyrighted novel. However, Colting's novel added unique plot elements such as working Salinger himself in as a character with whom the elderly Caulfield interacts.
Salinger sued Colting for copyright infringement. If you were Colting, what would you argue in an attempt to avoid liability? How do you think this case turned out?