Recent financial fraud legislation such as the Dodd–Frank Act and the Sarbanes–Oxley Act (U.S. House of Representatives, Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010, [H.R. 4173], 2010 ; U.S. House of Representatives, The Sarbanes–Oxley Act of 2002, Public Law 107-204 [H.R. 3763], 2002 ) relies heavily on whistleblowers for enforcement, and offers protection and incentives for whistleblowers. However, little is known about many aspects of the whistleblowing decision, especially the effects of contextual and wrongdoing attributes on organizational (...) members’ willingness to report fraud. We extend the ethics literature by experimentally investigating how the nature of the wrongdoing and the awareness of those surrounding the whistleblower can influence whistleblowing. As predicted, we find that employees are less likely to report: (1) financial statement fraud than theft; (2) immaterial than material financial statement fraud; (3) when the wrongdoer is aware that the potential whistleblower has knowledge of the fraud; and (4) when others in addition to the wrongdoer are not aware of the fraud. Our findings extend whistleblowing research in several ways. For instance, prior research provides little evidence concerning the effects of fraud type, wrongdoer awareness, and others’ awareness on whistleblowing intentions. We also provide evidence that whistleblowing settings represent an exception to the well-accepted theory of diffusion of responsibility. Our participants are professionals who represent the likely pool of potential whistleblowers in organizations. (shrink)