|posse comitatus (ˌkɒmɪˈtɑːtəs)|
|the formal legal term for posse|
|[Medieval Latin: strength (manpower) of the county]|
ancient English institution consisting of the shire's force of able-bodied private citizens summoned to assist in maintaining public order. Originally raised and commanded by the sheriff, the posse comitatus became a purely civil instrument as the office of sheriff later lost its military functions. From time to time, legislation gave authority to other peace officers and magistrates to call upon the power of the county.
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