Breach of law or act offending common decency

If the purpose of performance was determined in such a way that the recipient, in accepting it, was violating a statutory prohibition or offending common decency, then the recipient is obliged to surrender the performance. A claim to return is excluded if the person who rendered performance likewise was at fault for such a breach, unless the performance consisted in entering into an obligation; restitution may not be demanded of any performance rendered in performing such an obligation.