If I suspect a person has fraudulently obtained a medical certificate (by omitting/lying on MedXpress and to the AME) how can the person be reported? I need to remain anonymous.
In general, no. To aid and abet one must take some action, knowing that an act is a crime, to help it happen. To be an accessory, one must help or assist the criminal in some way, even if after the fact.
We are not all obligated to be policemen. People in some roles are obligated to report certain types of crime. I don’t believe pilots have such obligations regarding others.