This research-in-progress paper focuses on the development of a threat model for maintaining whistleblower anonymity. Citizens have the obligation to uphold ethical behavior and report behavior that violates their personal and professional code of ethics. Whistleblowers are those who release information to expose the wrongdoings of a company or individual. When choosing how to report, the whistleblower must consider various reporting channels. However, due to the likelihood of retaliation, whistleblowers must also be aware of threats to their anonymity. Therefore, anonymous whistleblowers must take actions to protect themselves from threat actors and threat vectors that might expose their identity. With these issues in mind, our goal is to develop a comprehensive threat model for anonymous whistleblowing, as well as provide whistleblowers with a systematic approach to maintaining their anonymity throughout the whistleblowing process.