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The Postal Police force includes uniformed bargaining-unit Postal Police Officers (PPOs) and non-bargaining supervisory and managerial Postal Police personnel. Postal Police Officer operations are under the administrative control of the United States Postal Inspection Service (USPIS), the law enforcement and security arm of the U.S. Postal Service.
PPOs are represented by a union, the Postal Police Officers Association. The PPOA collectively bargains with the U.S. Postal Service over hours, wages, and working conditions for PPOs.