From USAJOBS Help
There are appointing authorities not regulated by the Office of Personnel Management.
- Postal Career Service Employees – Authorities: 39 U.S.C. 1006
- Postal Rate Commission Employees – Authorities: 39 U.S.C. 3604(e)
Using these authorities, an agency may appoint an eligible individual to any position for which the person meets the qualification standard and other requirements governing appointment to the competitive service, without having to compete in a competitive examination. The individual is also not required to compete with career and career-conditional employees under internal merit staffing procedures unless an agency's policies require the individual to do so. The agency must verify applicant eligibility.