The OIG’s Special Inquiries Division (SID) conducts criminal and administrative investigations covering four primary areas: Internal Affairs, Special Inquiries, Whistleblower Reprisal, and Workplace Environment.


Internal Affairs investigates allegations of administrative and/or criminal misconduct against all USPS OIG personnel and all Postal Inspection Service personnel. This includes sworn law enforcement officers (OIG Special Agents, Postal Inspectors, and Postal Police Officers), as well as all professional, management, and support staff.

To file a complaint against a USPS OIG or Postal Inspection Service employee, please visit the OIG Hotline for reporting options.


Special Inquiries investigates allegations of administrative and/or criminal misconduct against Postal Service executives in the Postal Career Executive Series (PCES). PCES is substantially similar to the federal Senior Executive Series (SES).

In the Postal Service, PCES-level executives include certain senior officials in the Postal Service customer service districts and areas, Officers of the Postal Service, the Postmaster General, and the Postal Service’s Board of Governors.

To report potential misconduct by a PCES-level executive, please visit the OIG Hotline for reporting options.


The Whistleblower Reprisal Unit investigates allegations of reprisal or retaliation made by Postal Service employees and contractors, Postal Inspection Service employees and contractors, and USPS OIG contractors. Allegations of reprisal or retaliation by USPS OIG employees are investigated by an independent contractor to ensure impartiality.

The Postal Service is not covered by the Whistleblower Protection Act, but does have its own policy governing whistleblower retaliation. This policy is located in the Postal Service’s Employee and Labor Relations Manual.

Postal Service policy prohibits retaliation against an employee because the employee (or applicant for employment) disclosed information the employee (or applicant) reasonably believes involves:

  • A violation of any law, rule, or regulation, or
  • A gross waste of funds, gross mismanagement, an abuse of authority, or a substantial and specific danger to public health or safety.

There can be no reprisal for disclosures to the Office of Inspector General, unless the complaint was made or the information disclosed with the knowledge that it was false or with willful disregard for its truth or falsity.

To report potential whistleblower reprisal, please complete the OIG’s online Whistleblower Complaint Form or visit the OIG Hotline page for other reporting options.


The Workplace Environment Unit reviews workplace environment and operational issues in Postal Service facilities throughout the country, including at the OIG and Postal Inspection Service. These reviews identify and focus on systemic (rather than individual) issues and ensures that Postal Service management continues efforts toward providing employees a stress- and adversity-free work environment.

OIG workplace environment reviews may result in fact-finding reports to management or referral for specific suggested action, such as workplace climate assessments. Examples of areas examined include hostile work environments, sexual harassment, discrimination, nepotism, favoritism, intimidation, and workplace safety.

Workplace environment complaints can be submitted by any Postal Service, OIG, or Postal Inspection Service employee. To see what the types of workplace environment complaints the OIG does and does not investigate, or to report a potential workplace environment concern, please visit the OIG Hotline.