Rumor-mongering is part of every high school experience. Hannah doesn't delve into her pre-high school past, but she does hint that she had a problem with her reputation in middle school. She considers her new high school in a new town a fresh start. Unfortunately, she becomes a target for rumors almost instantly at her new school, and once the rumors start, they just keep growing. Most of us have seen this ugly game in action and may have even played it – either by starting rumors, spreading them, becoming a victim of them, or all of the above.
This theme points to a controversial issue in the novel: Hannah, a clear victim of rumors, leaves behind even more rumors in her tapes. As we discuss in "Narrative Technique," all the information we get in the book is filtered through Clay and Hannah, both unreliable narrators. This is a real problem when we think about characters being accused of serious illegal activity, particularly Bryce, Tyler, Justin, and Jenny. It's a challenge for readers to remain objective about these characters (whose side of the story we don't hear) while still trusting our protagonists.
By the end of the novel, Clay learns that you don't have to spread rumors to harm someone – all you have to do is believe these rumors.
Clay's decision to risk his reputation and reach out to Skye Miller shows that Hannah's story has changed how he views the social jungle of high school.