This study investigates the use of military police from the American Revolution to the interwar period following World War I. Specifically discussed is the use and development of military police capabilities during the American Revolution, Civil War, and World War I. The use of military police during these wars establishes a cycle of entering into conflicts without military police resulting in the use of an ill prepared ad hoc force that ultimately creates a need to develop a dedicated military police element. This study examines why a permanent military police corps was not established following WWI despite the American Expeditionary Forces (AEF) creating a similar corps based on the requirements created by a large and complex war. This study emphasizes the need for a permanent military police corps as part of the overall United States (US) Army structure in order to maintain and improve a capability needed for future conflicts.