In one of the most wrenching scenes from “Making a Murderer,” special education student Dassey asks his interrogators to take him back to school after he implicates himself in a murder. If one rewinds his interrogation videotape, though, it’s easy to understand why Dassey thinks he’s going back to school: Earlier, police had falsely assured him that he’d be “all right” and have “nothing to worry about” as long as he told them a story that fit their own theories. But after he parroted back his interrogators’ theories of guilt, Dassey was arrested, not released.