A fraud investigation was completed by management, and a proven fraud was communicated to relevant...

According to IIA guidance, the most appropriate role for the internal audit activity after a fraud investigation is to conduct lessons learned sessions to ascertain how the fraud occurred and which controls failed. This approach helps the organization to understand the weaknesses in their controls and processes, thereby facilitating improvements to prevent future occurrences.

IIA Practice Advisories on fraud and the role of internal auditing post-investigation.