After observing a colleague's behavior, a medical assistant writes an email to a coworker expressing concerns that the colleague might be diverting narcotics from the clinic. The email is accidentally sent to a group mailing list, including the accused colleague. No investigation has taken place, and the allegations are based solely on suspicion. This situation can be construed as an example of what legal issue?
Invasion of privacy
Breach of confidentiality
Libel
Professional misconduct related to email use