Although the movie is titled "Slander", there is no evidence that any of the characters were a victim of that crime, which refers to a malicious false statement. From the evidence, all of the stories, particularly that of the hero, presented in the scandal magazine were true.
In addition to the statements the newspaper makes being true and therefore not defamatory--falsity is required for either slander or libel litigation--a false statement in a newspaper would be libel, which is written defamation, while slander is oral defamation.