Rebecca Tushnet, a law professor at Georgetown, founded the Organization for Transformative Works, a nonprofit focused on fandom. They were established to make a home for people who make non-commercial transformative works who face legal challenges and copyright battles.
People often assume that certain expression is illegal when it actually is not. When Rebecca first got into law, legal institutions and lawyers were just beginning to become aware of the internet. There was a fantasy of control and a notion that digital files would lead to an era of perfectly controlled content.
Rebecca investigated the legality of fan fiction and found that it is, indeed, legal. Legal questions surrounding the Further Adventures of Mulder & Scully have been mostly resolved. The writing that comprises fan fiction is fair use. [See the Center for Social Media’s Guide to Fair Use]