posse comitatus
posse comitatus (pos-ee kom-[schwa]-tay-t[schwa]s), n. [Latin “power of the county”] A group of citizens who are called together to help the sheriff keep the peace or conduct rescue operations. — Often shortened to posse. [Cases: Armed Services 3; Sheriffs and Constables 27. C.J.S. Armed Services §§ 7–10, 31, 33, 41; Sheriffs and Constables§ 49.]