You don't say what role you play within the organization, but assuming you are a member of the Board and you have not been able to resolve the issue through discussion with the falsifiers, the committee, or the chair of the Board, the next step is to raise the issue with the full Board. (If the organization has voting members and you fail to get resolution from the Board, you might want to take it up with the members.) If these efforts fail, you may have a potential lawsuit if there has been a violation of bylaws or formal policies, or a complaint to the District Attorney or Attorney General if there has been a violation of the law. You want to be very careful about either of these courses of action, however, because they can be costly and diverting, and because the publicity can seriously damage the organization and its mission. 

 

Assuming that your organization is not part of a system of other organizations, there is no organization that governs nonprofits generally, and the Attorney General is usually the only outsider with power to legally enforce proper governance. If none of these suggestions is appropriate or effective, at the very least you will want to record your dissent in the Board minutes if you disagree with any action taken on the basis of this falsification. You may ultimately have to decide whether the infraction is so significant that you have to resign.