Formerly, the central government possessed the right of mobilizing military personnel, but according to a theory, the system concerned was changed to the following one: An Oryoshi, a police and military command, was appointed to each province, and when instructed by Zuryo (the head of the provincial governors) who received an official document instructing the suppression of a rebellion, the Oryoshi mobilized samurai in the province to suppress the rebellion.
従来は中央政府に発兵権があったが、国毎に警察・軍事指揮官として押領使（おうりょうし）を任命し、中央からの「追討官符」を受けた受領の命令で押領使が国内の武士を動員して反乱を鎮圧する体制に移行したとする説がある。