Those who have been defrauded have a number of remedies available. One is to challenge the discharge by filing an adversary proceeding in the bankruptcy case. Under section 727 of the U.S. Bankruptcy Code, a discharge can be denied outright where there has been an attempt to hinder, defraud or to delay creditors. Under section 523, the particular item can be excluded from the discharge on grounds specifically set out in that section.
This answer is offered for informational purposes only. It is not offered as, and does not constitute, legal advice. Laws vary widely from state to state. You should rely only on the advice given to you during a personal consultation by a local attorney who is thoroughly familiar with state laws and the area of practice in which your concern lies.
Bankruptcy fraud is investigated by the office of the United States Trustee, often with the assistance of their sister agency, the FBI. You may report your suspicions of Bankruptcy fraud to the office of the United States Trustee in the community where the Bankruptcy was filed and they will investigate.
Keep in mind that honest people can disagree about what is and what is not fraud under the Bankruptcy laws.
If you feel that you have a claim against someone who has filed Bankruptcy, you may file an adversary action against them. However, keep in mind that an adversary proceeding is like any other lawsuit. Legal representation is expensive & if you lose, you can be held responsible for paying the other sides legal fees. Ouch!